Novatek-Electro UBZ-305M Documentation

https://www.overvis.com/docs/en/ubz-305m/

2026-04-06

1. Novatek-Electro UBZ-305M
2. UBZ-305M Operating Manual
3. Appendix A: Current Protection Curves
4. Appendix B: Star-Delta Starting

Novatek-Electro UBZ-305M

UBZ-305M Universal Motor Protection Unit

The UBZ-305M is a universal motor protection unit manufactured by Novatek-Electro, designed to protect three-phase AC induction motors from emergency conditions. It is a functional analogue of UBZ-305, but uses USB interface instead of RS-232 for PC connection.

Key Features

Motor power range: 2.5 to 315 kW (with external current transformers)
Voltage: 400 V, 50 Hz three-phase
Current transformer output: 5 A standard
Multiple protection types: Overcurrent, thermal overload, ground fault, phase sequence, voltage limits, frequency, and more
Temperature monitoring: Two temperature sensor inputs (PTC, Pt100, Ni100, Ni120)
Communication: USB and RS-485 interfaces with MODBUS protocol
Motor insulation monitoring: Built-in insulation resistance measurement
Analog inputs: 0-20 mA and 0-10 V inputs for external sensors
Energy metering: Total, active, and reactive energy measurement
DIN rail mounting: Standard 35 mm DIN rail installation

Protection Functions

The UBZ-305M provides comprehensive motor protection including:

Low-quality network voltage (surges, phase failure, incorrect phase sequence, phase imbalance, frequency deviation)
Mechanical overloads (symmetrical overload in phase/line currents)
Negative-sequence current threshold crossing
Phase current unbalance without overload (motor/cable insulation fault detection)
Torque failure on motor shaft (“dry running” protection)
Motor delayed start or rotor blocking
Low insulation resistance between stator and motor housing
Ground fault during operation (ground leakage current protection)
Motor thermal overload
Winding overheating (via built-in or external temperature transmitters)

Common Use Cases

High-power industrial motor protection
Pump and compressor safeguards
HVAC system motor control
Conveyor and fan motor protection
Process automation applications

Documentation

Operating Manual – Complete operating instructions, installation, and configuration

Technical Reference

Appendix A: Current Protection Curves – Current protection with dependent time delay curves
Appendix B: Star-Delta Starting – Motor control with winding changeover

Technical Specifications

Parameter	Value
Operating supply voltage	400 V, 50 Hz (three-phase)
Mains frequency range	48 - 62 Hz
Rated current of CT	5 A
Operating temperature	-20 to +55°C
Protection level	IP 20
Dimensions (H×W×L)	91×157×58 mm
Weight	0.34 kg max
Wire cross section	0.5-2 mm²

UBZ-304 – Similar motor protection unit with RS-232 interface
UBZ-302M – Compact motor protection device

Support

Knowledge Base: Browse this documentation for detailed guides and references
Support Center: Visit our Support Center for FAQs and troubleshooting
Report an Issue: Submit a support ticket for technical assistance

Novatek-Electro UBZ-305M Documentation

UBZ-305M Operating Manual

Novatek-Electro UBZ-305M Universal Motor Protection Unit

This Operating Manual is intended to familiarize you with the unit, the requirements for safety, operation and maintenance procedures of the universal motor protection unit UBZ-305M (hereinafter referred to as UBZ-305M or unit).

During operation and maintenance, the regulatory document requirements must be met, namely:

Regulations for Operation of Consumer Electrical Installations
Safety Rules for Operation of Consumer Electrical Installations
Occupational Safety when in Operation of Electrical Installations

Installation, adjustment and maintenance of the Unit must be performed by qualified personnel having studied this Operating Manual.

In compliance with the requirements of this Operating Manual and regulations the Unit is safe for use.

The Unit meets the requirements of the following international standards:

EN 60947-1
EN 60947-6-2
EN 55011
EN 61000-4-2

Abbreviations and Terms

Abbreviation	Meaning
ARS	Automatic restarting
MS	Magnetic starter
PC	Personal computer
CT	Current transformer
LCD	Liquid crystal display
MNS	Minimum number of settings (it is used in phrases as MNS mode or MNS list)
Iсt	Rated current of CT (it is set when external CTs using; e.g., if CТ is of Т-0.66 300/5 type, then Iсt equals to 300 A)
In	Rated current of the motor; As a rule, this value of current is indicated on the motor nameplate, but depending on the operating conditions, the different value of current can be set
S.c.	Short circuit

1. Application

1.1 General

UBZ-305M is a functional analogue of UBZ-305. But as to connection with PC, UBZ-305M uses USB interface instead of RS-232.

UBZ-305M is designed for protection of induction motors with power of 2.5 to 315 kW in case of using the external standard current transformers with 5A output current.

UBZ-305M can be operated in networks both with insulated and dead grounded neutral.

The unit is of DIN rail design version.

UBZ-305M provides continuous monitoring of mains voltage parameters, current values of the phase (line) currents of three-phase electrical equipment for 400 V, 50Hz, and checking the resistance values of motor insulation.

UBZ-305M provides protection of electrical motors in case of:

low-quality network voltage (unacceptable power surges, phase failure, incorrect phase sequence and phase “coincidence”, the imbalance of phase/line voltages, the reduction in the network frequency lower than the set one and (or) the increase of network frequency higher than the set value);
mechanical overloads (symmetrical overload in phase/line currents);
the threshold crossing of the negative-sequence current;
unbalance of phase currents without overload associated with the insulation fault inside motor and/or the power cable (the comparison of current unbalance factor according to inverse sequence with voltage unbalance factor according to inverse sequence);
the torque failure on the motor shaft (“dry running” for pumps) – protection based on the minimum starting and/or operating current;
motor delayed start or rotor blocking;
extremely low isolation between the stator and the motor housing (pre-startup check);
ground fault of the stator winding during operation – ground leakage current protection;
motor thermal overload;
overheated windings (temperature of windings is determined using the motor built-in temperature transmitters or the temperature of the housing when using the external temperature transmitters).

For each type of protection it is possible to have banning and permitting of automatic restarting (hereinafter referred to as ARS) with load.

UBZ-305M provides for electric equipment protection by means of controlling the coil of the magnetic starter (contactor).

UBZ-305M detects motor currents when load relay is off (when the load relay is off and functional relay is in star-delta mode). In this case, UBZ-305M indicates the fault of external contactor starting the motor until UBZ-305M is turned off or control of motor currents is disabled when load relay is off.

UBZ-305M provides for electric motors control:

using analog inputs “0-20 mA” and “0-10 V”;
using remote control channels (USB and RS-485 interfaces);
by buttons on the front panel of UBZ-305M.

Communication

UBZ-305M provides:

Control and transfer of parameters via RS-485 interface in compliance with MODBUS Protocol, and
Control and transfer of parameters via USB interface.

For UBZ-305M to work with PC, you can use the program “Control Panel UBZ-304/305”, published on the “Novatek-Electro” website (https://novatek-electro.com/en/software/control-panel-of-ubz-304305.html)

The Program “Control Panel UBZ-304/305” has been designed to monitor the status and collect data from UBZ-305M via USB or RS-485 communication interfaces (MODBUS Protocol).

The program allows you to save (load) various settings of the device, collect data and save them for further analysis. The saved data can be viewed as graphs comparing the parameters with each other.

The graphical interface of the control panel allows you to monitor the current state of various Unit parameters in real time. The flexible interface configuration permits you to adapt to the requirements of any user.

1.2 Operating Conditions

UBZ-305M is designed for operation in the following conditions:

Ambient temperature: from minus 20 to +55°С
Atmospheric pressure: from 84 to 106.7 kPa
Relative air humidity (at temperature of +25°С): 30 … 80%

If the temperature of the unit after transportation or storage is different from the temperature of the environment in which its operation is assumed, then before connecting to the mains keep the unit in operation conditions for two hours (because on the unit elements condensation may be available).

1.3 Changes in the Characteristics and Operation of UBZ-305M Depending on Program Version

If the software version is 10 or less, then changes in UBZ-305M characteristics and operation are not available.

1.4 Controls and Overall Dimensions

1.4.1 Design

Overall dimensions of UBZ-305M are given in Figure 1.1.

UBZ-305M Overall Dimensions

Figure 1.1 – Overall Dimensions of UBZ-305M

1.4.2 Indication and Controls

Controls of UBZ-305M are given in Figure 1.2.

UBZ-305M Controls

Green LED “Function” is on when functional relay is on
Green LED “Motor”:
- is on when load relay is enabled
- flashes if UBZ-305M is within hysteresis band when controlling using analog inputs
Green LED “Ｙ/△” is on when UBZ-305M functional relay operates in star-delta mode (see section 2.5.3)
Green LED “TR” is on when UBZ-305M functional relay operates in time-delay relay mode
Red LED “FAULT”:
- when load relay is off: it is on when UBZ-305M is in fault conditions (it flashes if after fault ARS is expected)
- when load relay is on: it flashes when the motor is in conditions of over-current or thermal overload but relay off time has not come yet
Blue LED ”⇄” is on when data exchange with PC occurs
Connector for UBZ-305M to a PC via USB
Button UP – scrolling of displayed parameters in the parameter view mode and scrolling of the menu in the parameters setting mode
Button DOWN – scrolling of displayed parameters in the parameter view mode and scrolling of the menu in the parameters setting mode
Green LED “MMSP” is on when the relay is in MNS mode
Button “WR/SEL” – parameters recording in the setting mode, switching over the group of displayed parameters in the view mode, reset
Button “SETUP” – turns on the parameters setting mode
Red LED “SETUP” is on when UBZ-305M is in the mode of parameters setting
LCD

Figure 1.2 – Controls of UBZ-305M

2. Components

Delivery set is given in Table 2.1.

Table 2.1 – Delivery Set

Description	QTY
UBZ-305M	1
Differential transformer (zero sequence transformer)	1
Cable for communication with PC via USB (type USB type A – microUSB type B)	1
Temperature transmitter (types: Pt100, Ni100, Ni120) *	1
Operating manual	1
Packing	1

* delivered by agreement with the buyer for a separate fee

3. Specifications

3.1 Basic Technical Specifications

Basic technical specifications of UBZ-305M are given in Tables 3.1 and 3.2; specifications of contacts of built-in relays are shown in Table 3.3.

Table 3.1 – General Data

Description	Value
Application of the unit	Switchgear and control-gear; induction motor protection control
Design (installation) type	DIN rail 35 mm
Protection level	IP 20
Climatic version	NF 3.1
Operating temperature range*	from minus 20 to +55°С
Contamination level	II
Overvoltage category	II
Rated voltage of insulation	450 V
Rated impulse withstand voltage	2.5 kV
Electric shock protection class	II
Wire cross section for connection to terminals	0.5-2 mm²
Torque for terminal screws	0.4 N·m

*Note: It is allowed UBZ-305M operation at temperatures from minus 35 to minus 20°С; in this case the readings on display can be not available.

Table 3.2 – Technical Specifications

Description	Value
Operating supply voltage, three-phase	400 V, 50 Hz
Mains frequency	48 - 62 Hz
Rated current of CT	5 A
(Phase/line) voltage hysteresis	10/17 V
Heat hysteresis, in % of accumulated heat in case of shutdown	33
Determination accuracy of trip threshold for current, in % of rated value, not more	2
Determination accuracy of trip threshold for voltage, V, not more	3
Determination accuracy of out-of-phase voltage V, not more	3
Voltage when maintaining serviceability:
- phase voltage, when powered by one phase and zero wire is connected, V, not less	180
- line voltage, when powered by three phases, V, not more	450
Analog inputs:
- input to connect temperature transmitter (types: Pt100, Ni100, Ni120), pc.	1
- input to connect temperature transmitter of PTC-1000 type, pc.	1
- three analog inputs for standard CT with 5A output (T-0.66 type or similar), pc.	3
- input to connect differential current transformer (zero sequence transformer), pc.	1
- input to measure current of 0-20 mA, pc.	1
- input to measure voltage of 0–10 V, pc.	1
Main outputs:
- load relay – two groups of changeover contacts to control the electric motor starter	8 A, 250 V at cos φ=1
- functional relay – one group of changeover contacts (function of the relay is set by the user)	16 A, 250 V at cos φ=1
Permit according to temperature of temperature transmitters	1°С
Power consumption (under load), VA, not more	5.0
Weight, kg, not more	0.34
Overall dimensions (H×W×L), mm	91×157×58
Position in space	free
Housing material	self-extinguishing plastic

Table 3.3 – Characteristics of Built-in Relay Output Contacts

Relay	Max. current at U~250V	Number of actuations ×1000	Max. switching power	Max. continuous boosting AC/DC voltage	Max. current at Ucont=30V
Functional relay Cos φ = 0.4	5A	100	4000 VA	440/300 V	5 A
Functional relay Cos φ = 1.0	16A	100	4000 VA	440/300 V	5 A
Load relay Cos φ = 0.4	2A	100	2000 VA	460 V	3 A
Load relay Cos φ = 1.0	8A	100	2000 VA	460 V	3 A

3.2 Measured, Calculated, Special and Service Parameters

Special and service parameters are intended only for transmission using MODBUS interface (RS-485/USB). Special and service parameters are given in Table 3.4.

Measured and calculated parameters the values of which are displayed on LCD display, limits of their measurements and accuracy are given in Table 3.5.

Parameter values can be transferred to PC connected to one of the UBZ-305M interfaces (MODBUS, USB). Parameter addresses are indicated in Table 3.5.

Table 3.4 – Special and Service Parameters

Measurement functions	Range	Remarks	Address
Heat balance of the motor	The number 1100000 corresponds to 100% of accumulated heat at which the motor is switched off when the thermal overload protection is enabled (section 3.4.7)	Read-only parameter of USB, RS-485 interface	73, 74
Index of the last fault in the fault logbook	It varies from 0 to 49, increasing by one after recording another fault in the fault logbook. When the number of faults will reach 50, the count of faults will begin again from scratch.	Read-only parameter of USB, RS-485 interface	75

Table 3.5 – Measured and Calculated Parameters

Currents

Measurement functions	Range	Accuracy	Mnemonic	Address	Data transfer units
Effective values of phase currents, A	0.5 – 6300	2%	Phase i1, Phase i2, Phase i3	30, 31, 32	The tenth of amperes. When working with measuring transformers with rated current over 100 A, the currents (measured and calculated) in addition to the zero sequence current (ground fault) are transferred via USB/RS485 in amperes
Effective value of positive-sequence current, A	0.5 – 6300	2%	Positive si	33
Effective value of zero-sequence current, A	0.3 – 20	2%	Earth i0	34
Negative-sequence current (imbalance), A	0.2 – 200	5%	Revers si	35
Average current per each phase during the time specified in the parameter “Tm average I”			Average i1, Average i2, Average i3	36, 37, 38
Maximum value of the average current for each phase obtained since the last download. Reset of all average values is performed by the button WR/SEL in case of displaying the maximum value of average current in any phase	<3 Iсt: 2%, >3 Iсt: 10%		Peak i1, Peak i2, Peak i3	39, 40, 41
Motor starting current (average phase current)	<3 Iсt: 2%, >3 Iсt: 10%		Start i	42
Overload current (average phase current)			Overload i	43
Starting time, s (time from when all three-phase current will exceed 1.2 In and up to the moment when three currents will drop lower than 1.2 In)	0.1 – 600		Start time	44

Voltage

Measurement functions	Range	Accuracy	Mnemonic	Address	Data transfer units
Effective values of phase voltages (determined when connecting the neutral conductor to UBZ-305M), V	100 – 300	3V	Phase U1, Phase U2, Phase U3	45, 46, 47	Volt
Effective values of line voltages, V	100 – 475	5V	Line U1, Line U2, Line U3	48, 49, 50	Volt
Positive-sequence voltage, V	100 – 300	3V	Positive sU	51	Volt
Negative-sequence voltage, V	3 – 300	3V	Revers sU	52	Volt
Zero-sequence voltage (vector sum of three phase voltages divided by three), V	3 – 100	3V	Zero sU	53	Volt

Miscellaneous

Measurement functions	Range	Accuracy	Mnemonic	Address	Data transfer units
Time counter of motor operation, day	0 – 999		Time motor	54
Motor insulation resistance¹, MΩ	0 – 19.9	10%	Insulation	55	Hundreds of kOm
Mains frequency, Hz	45 – 65	1%	Frequency	56	Tenths of Hertz
Hold time before automatic restart², s	0 – 900	1 s	End of AR	57	Second
Time to overload trip³, s	0 – 600	1 s	Before OvL	58	Second
Waiting time after overload trip³, s	0 – 900	1 s	After OvL	59	Second
Full power⁴, kVA	0 – 5000	5%	Apparent P	60, 61	Dozens of Watts
Active power⁴, kW	0 – 5000	5%	Active P	62, 63	Dozens of Watts
Reactive power⁴, kVAr	0 – 5000	5%	Reactive P	64, 65	Dozens of Watts
Cosine of angle between voltage and phase current L1	0 – 1	5%	Cos A	66	Cosine × 1000
Cosine of angle between voltage and phase current L2	0 – 1	5%	Cos B	67	Cosine × 1000
Cosine of angle between voltage and phase current L3	0 – 1	5%	Cos C	68	Cosine × 1000
Temperature of transmitter 1⁵, °C	minus 40 – 80	1°C	Temp dat 1	69	5000 – transmitter is off; 1000±10 – s.c. of transmitter; 2000±10 – transmitter breakout
Temperature of transmitter 2⁵, °C	minus 40 – 220	1°C	Temp dat 2	70
Current value at analogue input “4-20 mA”, mA	0 – 25	2%	Input i	71
Voltage value at analog input “0-10 V”, V	0 – 10	2%	Input U	72
Full electric power⁶, kVA/h	0 – 200000000	5%	ApE	90, 91
Active electric power⁶, kW/h	0 – 200000000	5%	AcE	92, 93
Reactive electric power⁶, kVAr/h	0 – 200000000	5%	ReE	94, 95

Notes:

If the insulation resistance of the motor is more than 20 MOm, then the value indicator displays code “>20M”. When the motor is running (energized motor) the insulation resistance is not defined and the code indicator displays ”---” (when measuring circuit of motor insulation connecting).
If ARS is disabled, the indicator displays “not”.
If the time before shutdown by thermal overload protection or waiting time before permit to start-up is not defined (more than 900 s), then the value indicator displays code “undef”. If the protection function is disabled, the indicator displays “not”.
If the power consumed by the load is more than 999 kW (kVA, kVAr), the values of power are displayed with MW (MVA, MVAr).
If the temperature value exceeds specified limits, then the indicator displays the alarm code in accordance with Table 5.13. If the temperature sensor is disabled by software, then the indicator instead of temperature values displays “Off”.
In excess of the energy meter of the value 200,000,000, the counter is reset and the energy metering will start from zero. Recording the current values of the energy in the non-volatile memory is performed every 15 min.

3.3 Programmable Parameters

Programmable parameters and their variation limits are given in Table 3.6.

Table 3.6 – Programmable Parameters

Real Time Setting

Settings and readings	Parameter on LCD	Min. value	Max. value	Factory setting	Message on LCD, actions	Address
Set the current time	Real Time				Setting of current time and date (see section 5.3.8)	See Table 5.9

Transformers

Settings and readings	Parameter on LCD	Min. value	Max. value	Factory setting	Message on LCD, actions	Address
Rated output current of used CT, A	CT out i	1	5	5		151
Rated current of CT, A	CT nom i	20	800	100		152

Basic Parameters

Settings and readings	Parameter on LCD	Min. value	Max. value	Factory setting	Message on LCD, actions	Address
Rated current of motor, A	Rated Inom	0	630	0	0 – current is not set: UBZ-305M will not enable the load relay (see section 5.2.7)	150
Time during which the average current is measured, s	Tm average i	10	600	60	Time during which the average current is measured (parameters: “Average i1”, “Average i2”, “Average i3” of Table 3.5)	153

Over-current Protection

Settings and readings	Parameter on LCD	Min. value	Max. value	Factory setting	Message on LCD, actions	Address
Type of over-current protection	Type Imax	0	5	0	0 – “Indep” - protection with independent time delay. Types with dependent time delay: 1 – “SIT”; 2 – “VIT (LTI)”; 3 – “EIT”; 4 – “UIT”; 5 – “RI”.	154
Actuation setting for over-current protection, repetition factor	Imax coef	0.8	9	4	Repetition factor is set relative to rated motor current (used at “Type Imax” = “indep”)	155
Current protection delay tripping, s	Imax delay	0.3	600	10.0		156
Permit for protection operation	Imax protec	0	2	2	0 – “Off” – protection is off; 1 – “OnnAR” – protection is on, ARS after tripping is disabled; 2 – “On AR” – protection is on, ARS is enabled	157
Sequence of tripping relative to overheating protection	Imax<>T	0	1	1	0 – “On” – tripping regardless of overheating protection; 1 – “Ind” – if there is no overheating, then over-current indicating displays but load relay is not disabled	158

Ground Fault Protection (for zero-sequence current – I earth)

Settings and readings	Parameter on LCD	Min. value	Max. value	Factory setting	Message on LCD, actions	Address
Over-current tripping setting, A	I earth tresh	0.3	10	0.5	If not in MNS mode list: 0.5 at In≤50A; 1.0 at In>50A	159
Tripping delay, s	I earth delay	0.3	2	1		160
Permit for protection operation	I earth protec	0	2	2	0 – “Off” - protection is off; 1 – “OnnAR” - protection is on, ARS after tripping is disabled; 2 – “On AR” - protection is on, ARS is enabled	161

Negative-sequence Current Protection

Settings and readings	Parameter on LCD	Min. value	Max. value	Factory setting	Message on LCD, actions	Address
Actuation setting, %	I2 rev tresh	5	20	10	Set as percentage of rated current	162
Tripping delay, s	I2 rev delay	0.3	10	5		163
Permit for protection operation	I2 rev Protect	0	2	2	0 – “Off” - protection is off; 1 – “OnnAR” – protection is on, ARS after tripping is disabled; 2 – “On AR” - protection is on, ARS is enabled	164

Analysis of Causes for Negative Sequence Current Tripping

Settings and readings	Parameter on LCD	Min. value	Max. value	Factory setting	Message on LCD, actions	Address
Ratio of exceeding negative-sequence current factor to negative-sequence voltage factor	A-s I2 coef	2	4	2		165
Permit for analysis	A-s I2 protec	0	1	1	0 – “Off” - analysis is off; 1 – “On” - analysis is on	166

Thermal Overload (Heat Model of the Motor)

Settings and readings	Parameter on LCD	Min. value	Max. value	Factory setting	Message on LCD, actions	Address
Permit for protection operation	Termal OL protec	0	2	2	0 – “Off” - protection is off; 1 – “OnnAR” – protection is on, ARS after tripping is disabled; 2 – “On AR” – protection is on, ARS is enabled	167
Operating time of protection in case 2 time over-current, s	Termal delay	10	120	60		168
Factor of time increasing if motor is stopped	Termal C stop	1	4	1	Compensation of cooling time increasing while motor is stopped	169

Minimum Phase Current

Settings and readings	Parameter on LCD	Min. value	Max. value	Factory setting	Message on LCD, actions	Address
Actuation setting, %	Imin tresh	11	90	20	Operation threshold for the minimum operating current protection, in % of installed rated one	170
Tripping delay, s	Imin delay	1	100	5		171
Permit for protection operation	Imin protec	0	2	2	0 – “Off” – protection is off; 1 – “OnnAR” – protection is on, ARS after tripping is disabled; 2 – “On AR” – protection is on, ARS is enabled	172

Delayed Start, Rotor Blocking

Settings and readings	Parameter on LCD	Min. value	Max. value	Factory setting	Message on LCD, actions	Address
Actuation setting, repetition factor	Start I Coef	1.3	7	5	Repetition factor is set relative to rated current	173
Delayed start tripping delay, s	Start I delay	1	600	10	Time of motor starting	174
Rotor blocking tripping delay, s	Block I delay	0.3	300	1		175
Permit for protection operation	St/Block prot	0	2	1	0 – “Off” – protection is off; 1 – “OnnAR” – protection is on, ARS after tripping is disabled; 2 – “On AR” – protection is on, ARS is enabled	176

Voltage Protection

Settings and readings	Parameter on LCD	Min. value	Max. value	Factory setting	Message on LCD, actions	Address
Minimum line voltage, V	Umin tresh	270	415	320		177
Tripping delay for minimum line voltage, s	Umin delay	5	30	10		178
Permit for protection operation for minimum line voltage	Umin protec	0	2	2	0 – “Off” – protection is off; 1 – “OnnAR” – protection is on, ARS after tripping is disabled; 2 – “On AR” – protection is on, ARS is enabled	179
Maximum line voltage, V	Umax Tresh	330	450	415		180
Tripping delay for maximum line voltage, s	Umax delay	0.3	10	2		181
Permit for protection operation for maximum line voltage	Umax protec	0	2	2	0 – “Off” – protection is off; 1 – “OnnAR” – protection is on, ARS after tripping is disabled; 2 – “On AR” – protection is on, ARS is enabled	182
Line voltage imbalance, V	Uimbal tresh	15	120	35		183
Tripping delay for line voltage imbalance, s	Uimbal delay	1	30	5		184
Permit for protection operation for line voltage imbalance	Uimbal protec	0	2	2	0 – “Off” – protection is off; 1 – “OnnAR” – protection is on, ARS after tripping is disabled; 2 – “On AR” – protection is on, ARS is enabled	185
Permit for protection operation for phase sequence	Correct phase	0	2	1	0 – “Off” – protection is off; 1 – “OnnAR” – protection is on, ARS after tripping is disabled; 2 – “On AR” – protection is on, ARS is enabled	186

Motor Phase Loss with Current Control

Settings and readings	Parameter on LCD	Min. value	Max. value	Factory setting	Message on LCD, actions	Address
Tripping delay for phase loss, s	Phase LossT	0.3	10	0.5		187
Permit for protection operation	Phase Loss Prot	0	2	1	0 – “Off” – protection is off; 1 – “OnnAR” – protection is on, ARS after tripping is disabled; 2 – “On AR” – protection is on, ARS is enabled	188

Frequency Protection

Settings and readings	Parameter on LCD	Min. value	Max. value	Factory setting	Message on LCD, actions	Address
Minimum value of voltage frequency, Hz	Frequency Min	35	60	49.7		189
Tripping delay for minimum voltage frequency, s	FreqMin delay	1	300	10		190
Permit for protection operation for minimum voltage frequency	FreqMin prot	0	2	0	0 – “Off” – protection is off; 1 – “OnnAR” – protection is on, ARS after tripping is disabled; 2 – “On AR” – protection is on, ARS is enabled	191
Maximum value of voltage frequency, Hz	Frequency Max	50	65	51		192
Tripping delay for maximum voltage frequency, s	FreqMax delay	1	300	10		193
Permit for protection operation for maximum voltage frequency	FreqMax prot	0	2	0	0 – “Off” – protection is off; 1 – “OnnAR” – protection is on, ARS after tripping is disabled; 2 – “On AR” – protection is on, ARS is enabled	194

Motor Control and ARS

Settings and readings	Parameter on LCD	Min. value	Max. value	Factory setting	Message on LCD, actions	Address
ARS time after protection operation at minimum current, s	AR time Imin	1	900	600		195
ARS time, s	AR time	1	900	5		196
Disabled ARS for all faults (except voltage faults)	AR	0	1	1	0 – “Off” – ARS is disabled; 1 – “On” – ARS is enabled. AR parameter value covers all types of faults except voltage faults. To disable AR in case of voltage fault use “Umin protec”, “Umax protec”, “Uimbal protec”	197
Permit for motor operation after UBZ-305M energizing	Start>Power	0	2	1	0 – “StOff” – motor starting manually on UBZ-305M front panel; 1 – “St>AR” – motor starting after ARS time; 2 – “St>2s” – motor start after 2s.	198
Motor control on UBZ-305M front panel	MotorOp UBZ	0	3	0	0 – “Off” - it is disabled; 1 – “Start” – motor start is enabled; 2 – “Stop” – motor emergency shutdown is enabled; 3 – “St<>” – motor start-up and shutdown is enabled. See section 2.9	199
Motor remote start and shutdown via USB/RS485 interface	MotorOp RS-2/5	0	2	0	0 – “Off” – remote control is disabled; 1 – “OnSta” – remote control is enabled; motor start after UBZ-305M energizing is enabled after ARS time; 2 – “OffSt” – remote control is enabled, motor start after UBZ-305M energizing is disabled until the command for remote energizing	200

Temperature Control

Settings and readings	Parameter on LCD	Min. value	Max. value	Factory setting	Message on LCD, actions	Address
Permit for temperature control and type of temperature transmitter 1	Temp S1 Type	0	2	0	0 – “Off” – disabled; 1 – “R>1.7” – motor built-in type (protection enabled if transmitter resistance is above 1.7 Ω); 2 – “PTC” – PTC (1kΩ at 25°С)	201
Motor trip temperature	Temp S1 Off M	0	100	80		202
Temperature correction of the first transmitter	Temp S1 Corr	-9	9	0		203
Permit for temperature control and type of temperature transmitter 2	Temp S2 Type	0	3	0	0 – “Off” – disabled; 1 – “Pt100” – Pt100 type; 2 – “Ni100” – Ni100 type; 3 – “Ni120” – Ni120 type.	204
Motor trip temperature	Temp S2 Off M	0	220	180		205
Warning temperature	Temp S2 Alarm	0	220	170		206
Temperature correction of the second transmitter	Temp S2 Corr	-9	9	0		207
ARS after tripping	Temp AR	0	1	1	0 – “Off” – ARS is disabled; 1 – “On” – ARS is enabled	208
Temperature transmitters fault reaction	Temp Sens Fault	0	1	0	0 – “AonM” – warning and continuation of operation; 1 – “AoffM” – warning and motor stop	209

Motor Insulation Resistance

Settings and readings	Parameter on LCD	Min. value	Max. value	Factory setting	Message on LCD, actions	Address
Protection for the motor minimum insulation resistance	Insulation Mr	0	4	1	0 – “Off” – disabled; 1 – “5 AR” – motor not enabled when insulation <500 kΩ, ARS enabled; 2 – “10 AR” – motor not enabled when insulation <1000 kΩ, ARS enabled; 3 – “5 nAR” – motor not enabled when insulation <500 kΩ, ARS disabled; 4 – “10nAR” – motor not enabled when insulation <1000 kΩ, ARS disabled	210

Miscellaneous

Settings and readings	Parameter on LCD	Min. value	Max. value	Factory setting	Message on LCD, actions	Address
Activating the mode of minimum number of settings	Minimal set	0	1	1	0 – “Off” – mode disabled; 1 – “On” – mode enabled. Mode change possible only in advanced user mode	211
Indications on UBZ-305M display before starting the motor	Indicat <Start	0	1	0	0 – “LineU” – line voltage: “Line U1”, “Line U2”, “Line U3”; 1 – “InsFr” – motor running time, insulation resistance, mains frequency	212
Parameter display mode	Indicat mode	0	1	0	0 – “Conti” – parameter value displayed continuously; 1 – “>15s” – parameter value displayed for 15 s	213
Functional relay operating mode	Relay F mode	0	2	0	0 – “Alarm” – relay used as alarm relay; 1 – “Timer” – relay used as time relay; 2 – “St->D” – relay used for motor star–delta switching	214
Timer value, s	Relay F time	0	300	30	See “Relay F mode” parameter	215
Star-delta mode switching time, s	Delay RP RF	0.1	2	0.4	Time between load relay disabling and functional relay enabling in star-delta mode	216
Total time of the unit operation, day	Time UBZ	0	999	0	When transmitting by USB/RS-485 interface the operating time is transmitted in hours	217
Motor operating time, day	Time motor	0	999	0	When transmitting by USB/RS-485 interface the operating time is transmitted in hours	218
Access code of user	Users code	0	9	0	0 – keyboard is unblocked; 1-9 – user password	219
Access code of advanced user	Password	000	999	123	000 – access to advanced user level is permitted; 000-999 – advanced user password	220
Factory settings reactivating	Default Factor	0	1	0	0 – “Off”; 1 – “On”. After “On” and settings setup mode quit, factory settings will be reactivated (except advanced user access code)	221

Serial Interface Parameters (RS-485/USB)

Settings and readings	Parameter on LCD	Min. value	Max. value	Factory setting	Message on LCD, actions	Address
UBZ-305M communication address	Address UBZ	1	247	1		222
Transfer rate²	Data speed	0	1	0	0 – “9.6 k” – 9600 baud; 1 – “19.2k” – 19200 baud.	223
Converter reaction to loss of connection	Loss connect	0	3	0	0 – “non” – continuation without warning; 1 – “Alarm” – warning and continuation of operation; 2 – “StpAR” – warning and motor stop with ARS permit after restoring connection; 3 – “StpnA” – warning and motor stop with ARS disabled after restoring connection	224
Detection of response overtime, s	Overexceeding	0	120	0	0 – disabled	225
Permit of UBZ-305M communication via serial link	Communication	0	2	0	0 – “Off” – communication is disabled; 1 – “USB” – communication via USB; 2 – “RS485” – communication via RS-485	226
Type of communication protocol²	ASCII-RTU	0	1	1	0 – “ASCII”; 1 – “RTU” – MODBUS modes	227
Parity check²	Even parity	0	1	0	0 – “Off” – parity check disabled; 1 – “On” – parity check enabled	228
Number of stop bits²	Stop bit	1	2	2		229
Unit version	Version			9	Parameter value depends on software version	230
Indicator illumination¹	Indicator L	0	2	1	0 – “Off” – illumination is off; 1 – “On15s” – illumination on for 15 s after pressing any buttons; 2 – “On” – illumination on continuously	231
Clock correction, s	Correct Time	-10	10	0	Correction of the real time clock. Compensation of time for the day	232

Control via Analog Input 0-20 mA

Settings and readings	Parameter on LCD	Max. value	Factory setting	Message on LCD, actions	Address
Upper threshold, mA	Input I UP	20	10		233
Lower threshold, mA	Input I DOWN	20	1		234
Control algorithm	Input I ALG	2	0	0 – “Off” – control is off; 1 – “OffUP” – motor off when current higher than upper threshold, on when lower than lower threshold; 2 – “OnUP” – motor on when current higher than upper threshold, off when lower than lower threshold	235
Entry in faults logbook	Input I log	1	0	0 – “OffWr” – motor cutoff is the fault but not recorded in logbook; 1 – “OnWr” – motor cutoff is the fault and is recorded in logbook	236

Control via Analog Input 0-10 V

Settings and readings	Parameter on LCD	Max. value	Factory setting	Message on LCD, actions	Address
Upper threshold, V	Input U UP	10	5		237
Lower threshold, V	Input U DOWN	10	1		238
Control algorithm	Input U ALG	2	0	0 – “Off” – control is off; 1 – “OffUP” – motor off when voltage higher than upper threshold, on when lower than lower threshold; 2 – “OnUP” – motor on when voltage higher than upper threshold, off when lower than lower threshold	239
Entry in faults logbook	Input U log	1	0	0 – “OffWr” – motor cutoff is the fault but not recorded in logbook; 1 – “OnWr” – motor cutoff is the fault and is recorded in logbook	240
Serviceability check of external magnetic starter (MS)	Cont Cont	1	1	0 – “Off” – check disabled; 1 – “On” – check enabled	241
Energy meters reset	Energy RESET	1	0	0 – “Off”; 1 – “On” – reset	242

Notes:

Indicator light turns off if the line supply voltage is lower than 250 V.
Parameter change will happen after turning off and repeated energizing or fulfillment of “UBZ RESTART” command

3.4 Protection Functions

3.4.1 Protection Types

UBZ-305M performs the following protection types for electric motors:

over-current protection in phases
ground fault protection (for zero-sequence current)
for negative-sequence current
for exceeding negative-sequence current factor to negative-sequence voltage factor
for thermal overload
undercurrent protection in phases
delayed starting (rotor blocking)
overheating of windings
for minimum line voltage
for maximum line voltage
for line voltage imbalance (negative sequence voltage protection)
for improper phase sequence
for decreasing of mains frequency lower than setting
for increasing of mains frequency higher than setting
for minimum insulation resistance of the motor winding
for the motor phase loss (protection is operated when the motor current is disabled in one (two) phase)

3.4.2 Maximum Phase Current Protection

Maximum current protection on phase is three phase. It is enabled when one, two or three current values reach the actuation set-point.

The protection has time delay. The time delay can be definite (constant) or dependent (inverse-definite - SIT; very inverse-definite - VIT or LTI; extremely inverse-definite - EIT; ultra inverse-definite - UIT, time delay of RI type) - curves are shown in Appendix A.

Definite time delay protection

In case of the protection with definite time delay the motor is off when the current of one phase is more than specified for the time T (“Imax delay” parameter).

Is = “Imax coef” (tripping ratio) × “Rated Inom” (motor rated current), and T is the delay time of the protection operation (“Imax delay”).

Example: When “Imax coef” = 4.0, “Rated Inom” = 10, “Imax delay” = 10.0, the motor will switch off in 10 seconds after one of the phase currents exceeds 40 amp.

Figure 3.1 – Principle of protection with definite time delay

Protection with dependent time delay corresponds to the standards IEC 60255-3 and BS 142.

Dependent time delay protection

In corresponds to the set-point “Rated Inom” (motor rated current); T (“Imax delay” parameter is time constant of the protection operation) corresponds to time delay of tripping for 10×In. For very large currents the protection has a feature with definite time delay.

Figure 3.2 – Principle of protection with dependent time delay

Appendix A provides curves for the time constant of the protection to equal 1 second (“Imax delay” parameter). When setting the different value of the time constant, the response time of the protection is changed proportional to the time constant (for example, when “Imax delay” = 10 seconds, operating time of protection at the same ratio of currents will increase 10 times).

3.4.3 Ground Fault Protection

It is enabled when ground-fault current reaches the tripping threshold (“I earth tresh” parameter)
The motor switches off if the ground-fault current is more than specified for the time T (“I earth delay” parameter)

3.4.4 Negative-sequence Current Protection (Imbalance)

Negative-sequence current protection (imbalance) is enabled when a component of the negative sequence is more than the set-point (“I2 rev tresh” parameter) and stops the motor when time of this excess is more than specified value (“I2 rev delay” parameter).

If the analysis of tripping cause is enabled (“A-s I2 prot”=“On”), then in case of protection tripping due to exceeding of negative sequence current not because of line voltages imbalance (in this case the motor problems are assumed), ARS after tripping will not occur (regardless of the value of “I2 rev protec” parameter).

The coefficient of negative voltage (current) sequence is characteristic of unbalance of three-phase voltage (current). Approximately the coefficient of negative voltage sequence is determined by the formula:

$K_{2Ui} = \frac{U_{2(1)i}}{U_{1(1)i}} \cdot 100$

Where:

$U_{2(1)i}$ — RMS value of negative voltage sequence of fundamental frequency of three-phase voltage system in i-observation, V
$U_{l(1)i}$ — RMS value of positive voltage sequence of fundamental frequency in i-observation, V

$U_{2(1)i}$ is calculated by the approximate formula:

$U_{2(1)i} = 0.62(U_{nb(1)i} - U_{nm(1)i})$

where $U_{nb(1)i}$ , $U_{nm(1)i}$ are maximum and minimum RMS values of the three phase-to-phase voltage of the fundamental frequency in i-observation, V.

The coefficient of negative current sequence $K_{2Ii}$ is calculated similarly.

If currents imbalance is caused not by voltage imbalance, then motor fault is determined. To determine the cause of currents imbalance it is necessary to calculate the ratio of the coefficient of negative current sequence to the coefficient of negative voltage sequence ( $K_{2Ii} / K_{2Ui}$ ). And if the ratio is more than the value of “A-s I2 coef” parameter, then UBZ-305M considers that the motor has malfunction.

3.4.5 Minimum Phase Current Protection

It is enabled when the currents of all three phases drops lower than the set-point (“Imin tresh” parameter) and stops the motor when this drop time is more than the specified one (“Imin delay” parameter)
It is not active when the load current is less than 10% In (when decrease of the current is due to motor shutdown, not due to decrease of its load)
It has its own definite time delay of ARS (“AR time Imin” parameter)

3.4.6 Delayed Start and Rotor Blocking

The principle of delayed start protection and rotor inter-blocking is given in Figure 3.3.

Delayed start and rotor blocking

Delayed start

During start-up the protection is enabled when all phase currents are more than the set-point Is (“Start I Coef” parameter) during the period of time more than the ST time delay (“Start delay I” parameter).

Rotor blocking

After motor start performing (reducing the starting current lower than 1.2 of rated one) UBZ-305M switches to control of possible blocking of the rotor. The protection system operates when all the phase currents are more than set-points during a period of time greater than LT time delay (“Block I delay” parameter).

Figure 3.3 – Delayed start and rotor blocking

3.4.7 Thermal Overload Protection

Thermal overload protection is made on the basis of the equation solution of motor thermal balance under the following assumptions:

before the first start the motor was cold
during the motor operation, heat generates that is proportional to the square of the current
after motor turning off it is cooled down exponentially

For protection, you should enter the response time in case of double overload T2 (the parameter of “Thermal delay”).

For the standard recommended T2 value (60 s at 2 time overload) the following current-time characteristic applies:

Table 3.7 – Current-time characteristic

I/Inom	1.1	1.2	1.4	1.7	2	2.7	3	4	5	6	7	8	10	15
T (sec)	365	247	148	88.6	60	36.4	24.6	13.5	8.5	5.9	4.3	3.3	2.1	0.9

For rotating machines, cooling is more efficient during operation than during the stop of the motor, so enter the parameter “Thermal C stop” - the constant increase rate of cooling when the motor is stopped.

After the load relay disabling owing to thermal overload with ARS permitted, the relay will be enabled again after the time more than the maximum of the two values:

time of thermal hysteresis (motor should cool down to 33% of the accumulated heat)
time of ARS

Choosing different ARS time periods considering thermal hysteresis, one can reduce the number of starts per time unit because in the intermittent mode of operation UBZ-305M remembers the amount of heat released during the motor start.

Current-time characteristic

I/Iн – current ratio relative to rated one
Т/Т2 – the actual response time relative to T2 (response time when double overload)

Figure 3.4 – Current-time characteristic

3.4.8 Windings Overheating Protection

First input protection:

When working with motor built-in temperature transmitters (parameter “Temp S1 Type”=“R>1.7”) protection is enabled when the transmitter resistance will be more than 1700 Ω. Set-point “Temp S1 Off M” is not used: short-circuit and breakout of the transmitter is not controlled
When working with transmitters of PTC type (1kΩ at 25°C) (“Temp S1 Type” = PTC parameter), protection is enabled and stops the motor when the monitored temperature is more than the set-point (“Temp S1 Off M” parameter)

When working with PTC type transmitters, protection defines the cases of breakout and short circuit of the transmitter:

breakout at temperature higher than 100°C
short circuit at temperature less than minus 45°C

Second input protection:

It is enabled when the controlled temperature is higher than set-point
It has two independent set-points: the alarm set-point (“Temp S2 Alarm” parameter) and the set-point for the motor is off (“Temp S2 Off M” parameter)

Protection determines the cases of breakout and short circuit of the temperature transmitters:

breakout at temperature of more than 220°C
short circuit at temperature of less than minus 45°C

On the second input the protection is operated with temperature transmitters of Pt100 type (platinum type for 100 Ω at 0°C) or Ni100 (Ni120) (Nickel type for 100 Ω (120 Ω) at 0°C) in accordance with the standards of IEC 60751 and DIN 43760.

3.4.9 Voltage Protection

In UBZ-305M voltage protection before enabling the load it is necessary to check the corresponding set-points and depending on their value, the load relay enabling will be permitted or disabled; when the motor is on, the voltage control is fulfilled, but the decision relative to disabling is made according to currents.

The voltage protections are the following:

At minimum line voltage - enabled if at least one of the line voltages is less than the set-point (“Umin tresh” parameter) within the time specified by “Umin delay” parameter
At maximum line voltage - enabled if at least one of the line voltages is more than the set-point (“Umax tresh” parameter) within the time specified by “Umax delay” parameter
During line voltages imbalance - enabled if the difference between effective values of the line voltages is more than the set-point (“Uimbal tresh” parameter) within the time specified by “Uimbal delay” parameter

3.4.10 Phase Sequence Protection

Phase sequence protection (“Correct phase” parameter) is enabled in case of improper phase sequence; it disables the motor and blocks its further operation.

3.4.11 Network Power Frequency Drop Protection

Network power frequency drop protection is enabled if the network power frequency is less than the set-point (“Frequency Min” parameter) within the time specified by “FreqMin delay” parameter.

3.4.12 Network Power Frequency Rise Protection

Network power frequency rise protection is enabled if the network power frequency is higher than the set-point (“Frequency Max” parameter) within the time specified by “FreqMax delay” parameter.

3.4.13 Protection for Minimum Resistance of Motor Winding Insulation

After UBZ-305M energizing before the output relay will be on, it is necessary to check the insulation level of stator winding relative to the housing. The level of stator winding insulation relative to housing is also checked, when the load relay is on, but the motor currents are less than 10% of rated current (in this case UBZ-305M considers that the motor is off).

When “Insulation Mr” = “5 AR” (“5 nAR”) the load is disabled if the insulation resistance is lower than 500 kΩ ±20 kΩ, and when “Insulation Mr” = “10 AR” (“10 nAR”) if it is less than 1000 kΩ ±50 kΩ. During automatic restarting “AR”, the load will on after restoring the insulation resistance and after ARS time finishing. If “nAR”, ARS will not on.

3.4.14 Protection for Motor Phase Break (Loss)

Protection for the motor phase (-s) break (loss) is enabled if one of the motor phase current is more than 10% of the rated one (“Rated Inom” parameter), and any of the remaining phases of the motor is less than 7% of the motor rated current.

3.4.15 Serviceability Check of External Magnetic Starter

UBZ-305M detects the motor currents when the load relay is off (if the load relay and functional relay is off in star-delta mode). In this case, UBZ-305M indicates the fault of external MS enabling the motor, until then UBZ-305M is turned off or control of the motor currents is disabled when load relay is off (“Cont Cont” = 0 (“Off”) parameter).

4. UBZ-305M Design

UBZ-305M is microprocessor-based digital device that provides a high degree of reliability and accuracy. Operational power is not required. The controlled voltage is simultaneously the power supply voltage.

5. Intended Use

5.1 Preparation for Operation

5.1.1 Preparation for Connection

Unpack and check the Unit for damage after transportation; in case of such damages detection, contact the supplier or manufacturer
Check for components (section 2), in case of detection of incomplete Unit, contact the supplier or manufacturer
Carefully study the Operating Manual (pay special attention to the connection diagram to power the Unit)
If you have any questions regarding the installation of the Unit, please contact the manufacturer by telephone number indicated at the end of this Operating Manual

5.1.2 Selection of Current Transformers (CT)

Rated output current of CT should be 5 A
Rated input current of CT (Ict) is selected based on the rated current of the motor (In), the motor starting current, start duration, the time required for ARS (taking into account the characteristics of UBZ-305M inputs designed to connect CT (Table 5.1))

Table 5.1 – Characteristics of UBZ-305M inputs designed to connect CT

Current of UBZ-305M inputs designed for measurement of CT output currents, A	Ratio of overload relative to rated current (5 A)	Maximum duration of current action, s	Minimum delay before restarting, s
0 – 12	2.4	continuously	-
12 – 15	3	60	10
16 – 20	4	30	15
21 – 25	5	15	30

Rated input current of CT should be within the range: In < Ict < 3×In.

It is recommended to use CT with Ict = 2×In.

5.1.3 General

To ensure the reliability of electrical connections you should use flexible (stranded) wires with insulation for voltage of not less than 450V, the ends of which it is necessary to be striped of insulation for 5±0.5 mm and tightened with bootlaces. Recommended cable cross section for connection is not less than 1 mm².

Wires fastening should exclude mechanical damage, twisting and insulation abrasion of wires.

IT IS NOT ALLOWED TO LEAVE EXPOSED PORTIONS OF WIRE PROTRUDING BEYOND THE REMOVABLE TERMINAL BLOCK.

For reliable contact it is necessary to perform tightening of screws of removable terminal block with the force specified in Table 3.1.

When reducing the tightening torque, the junction point is heated, terminal block may be melted and wire can burn. If you increase the tightening torque, it is possible to have thread failure of terminal block screws or the compression of the connected wires.

5.1.4 UBZ-305M Connection

5.1.4.1 Connect the current transformers in accordance with Figure 5.1.

5.1.4.2 Pass through a differential current transformer (zero sequence transformer) all three phase wires and connect it to UBZ-305M.

5.1.4.3 To monitor and measure the motor insulation, connect the control terminal of the insulation 25 to one of output contacts of MS. If the motor housing is not grounded, or network with isolated neutral is used, or neutral wire is not connected to UBZ-305M terminal, it is necessary to connect electrically the motor housing to the terminal 26 of UBZ-305M.

5.1.4.4 Connect the motor to UBZ-305M in accordance with Figure 5.1. When using the motor with the switching over the windings during star-delta starting-up, perform the connection in accordance with Appendix B.

5.1.4.5 In case of MODBUS usage, connect the communication lines RS-485 to terminals 33 (GND), 34 (line B RS-485), 35 (line A RS-485) of UBZ-305M. Set the parameter of “Communication” = “RS485”.

UBZ-305M Connection Diagram

A – UBZ-305M
F1-F3 – Fusible element for 1 A (or its equivalent)
K – Magnetic starter (MS)
R1 – Temperature transmitter (for example: PT100)
R2 – Temperature transmitter (for example: PTC1000, EKS111 made by DANFOSS)
Q – Circuit breaker
QF – Circuit breaker at a maximum current of 6.3 A
T1-T3 – Current transformer (output 5 A)
T4 – Differential transformer

Figure 5.1 – UBZ-305M Connection Diagram

5.1.4.6 Energize UBZ-305M

The enabling sequence for the load relay after energizing is determined by the values of the parameters “AR time” and “Start>Power” (see section 5.3.1.1).

5.1.4.7 In the course of first starting in accordance with factory settings UBZ-305M is in the mode of MNS in which it is possible to set the following parameters:

CT rated current (parameter of “CT nom i”)
motor rated current (parameter of “Rated Inom”)

For normal operation of UBZ-305M it is enough to set these parameters according to used CT and the motor.

5.1.4.8 To operate the device together with PC as a control or monitoring device using the program “Control Panel UBZ-304/305”, it is necessary to:

Connect your PC to the Internet
Download on PC the file “Setupcplubz304_305(_X.X).exe” (X.X is the version number of the software) from the site of NOVATEK-ELECTRO (https://novatek-electro.com/en/software/control-panel-of-ubz-304305.html)
Install on PC “Control Panel UBZ-304/305” by running the file “Setup_cplubz304_305”

5.1.4.9 For the device to work with a PC via the USB interface, you must:

Connect your PC to the Internet
Upload the “USB-serial-Novatek.rar” file from the NOVATEK-ELECTRO website to your PC
Unpack the archive and install the driver on the PC by running the file “setup.exe”
Connect the “USB” connector on the device panel to the USB connector of PC using the “USB type A-microUSB type B” cable
Select “COM port” in the “Communication settings” section (“Settings” menu of the program “Control Panel UBZ-304/305”) the number of the appeared additional COM port and make sure that the other communication settings correspond to the UBZ-305M communication settings
Set the “Communication” parameter = “USB” in UBZ-305M

5.1.4.10 Disable power of UBZ-305M.

5.1.4.11 Connect the magnetic starter (hereinafter referred as MS) of the motor in accordance with Figure 5.1.

5.2 UBZ-305M Control

5.2.1 Modes of UBZ-305M Control and Status

UBZ-305M has five control modes:

Keyboard blocking
MNS
User level
Advanced user level
Remote control

All the modes of control have possibility to switch UBZ-305M in the state:

Viewing the measured and calculated parameters (Table 3.5)
Viewing the faults logbook (section 5.6)

5.2.2 Measured and Calculated Parameters View State

Measured and calculated parameters view state is the principal state. From all other modes UBZ-305M returns to this mode automatically (if after 30 s, no button is pressed).

In this mode the first three lines of the indicator displays a group of three functionally close settings (when adding the values of temperature transmitters or analog inputs – a group of two parameters) (Figure 5.2).

The information displayed in the fourth line of the indicator depends on the state of UBZ-305M.

If the load relay is enabled, then the fourth line of the display shows the current time (Figure 5.2).

UBZ-305M indicator - load relay on

The display shows:

In line 1 – current in phase A – 345 A
In line 2 – current in phase B – 350 A
In line 3 – current in phase C – 342 A
In line 4 – current time

Figure 5.2 – UBZ-305M Indicator in view mode of measured and calculated parameters (load relay is on)

If the load relay is off, then the fourth line of the indicator can display the following:

“AR=NOT Ir=0 15:30:17” in case if the motor start is impossible as the motor rated current is not set (parameter of “Rated Inom” =0)
“AR=NOT 15:30:17” in case if the fault occurred after which ARS is disabled
“AR=350 15:30:17” in case if the fault occurred and ARS is possible (ARS time account is on – 350 s left to ARS)

In the second and third variant, information of the fourth line of the indicator is consistently changing – in addition to reports about the possibility of starting the motor; it displays the total number of faults and type of fault on the display (Figure 5.3).

UBZ-305M indicator - fault condition

The display shows:

In line 1 – line voltage U1 – 345 V
In line 2 – line voltage U2 – 312 V
In line 3 – line voltage U3 – 210 V
In line 4 – “Imax” – type of fault (over-current protection); “Er 3:8” – the indicator displays the third fault; total number of existing types of faults is 8

Figure 5.3 – UBZ-305M Indicator in view mode of measured and calculated parameters (in fault conditions)

5.2.3 Mode of Keyboard Blocking

When the keyboard is blocked you cannot view and reinstall the programmable parameters.

When the keyboard is blocked, pressing the “SETUP” button leads to the appearance on the indicator the message “blocked buttons” (Figure 5.4).

Keyboard blocked indicator

Figure 5.4 – Indicator when the keyboard is blocked

To unblock the keyboard, it is necessary to press again the “SETUP” button. The led turns on “SETUP”, and the indicator displays the inscription “USERS PASSWORD” and “<0>”. With the help of UP and DOWN buttons you can dial the digit of user password from 1 to 9 and can press the button “WR/SEL”. If the password is correct, the keyboard is unblocked. If after unblocking the keyboard no button is pressed within 15 s and setting of blocking has not been disabled by the user, the keyboard is blocked again.

5.2.4 Mode of Minimum Number of Settings (MNS)

Mode of MNS is designed to facilitate the work of the service personnel with UBZ-305M.

In case of initial factory settings UBZ-305M is in the mode of MNS.

When UBZ-305M is operated in the mode of MNS the green led “MMSP” is on.

UBZ-305M operation in MNS mode differs from UBZ-305M operation in the mode of user level that the parameters not included in the list of MNS are set to factory defaults, and when you log in the user menu they are not visible.

Operation with parameters those are included in the list of MNS is the same as with the settings in the mode of user level (section 5.3.5).

When the mode of MNS is disabled (setting of parameter “Minimal set” is in “Off” position), the led “MMSP” goes out and UBZ-305M switches to the user level. At the user level you can change all the settings (included and not included in the list of MNS), if the change is not disabled by the advanced user.

UBZ-305M will transfer to the MNS mode after reset to factory settings (section 5.2.7).

5.2.5 Mode of User Level

When UBZ-305M unit is in the user-level mode, led “MMSP” is off.

To view and change the parameters of user level you should press the “SETUP” button, the led “SETUP” is on and the indicator displays the user menu (Figure 5.5).

Figure 5.5 – User Menu

Using DOWN and UP buttons select the desired parameter (in Figure 5.5, “CT nom i” parameter is selected; it is the rated current of the CT) and press the “SETUP” button (Figure 5.6).

User mode setting screen

Figure 5.6 – Screen of changing the setting in the user mode

If the fourth line of the indicator is marked by “ADV” (Figure 5.6), the change of the parameter value in the user mode is disabled and in this case it can only be changed in the mode of Advanced user level.

If the parameter is not in the list of MNS (the fourth line of the indicator has the inscription “OFF MMSP”), then to change the value of the parameter it is necessary preliminary to include it in the list of MNS. To do this:

using DOWN and UP buttons select the parameter
press “SETUP” button
press simultaneously DOWN and UP buttons (on the display instead of the inscription “OFF MMSP” the inscription “MMSP” should remain)

The value of the parameter in the user mode can be changed if the fourth line of the indicator has only the inscription “MMSP”. To do this:

using buttons DOWN or UP select the desired parameter value
using the button “WR/SEL”, record the value of the parameter, and to go back to menu without recording, press the “SETUP” button

If no button is pressed within 30 seconds, UBZ-305M switches to the state of the viewing the measured and the calculated parameters.

To exit to menu before 30 seconds you need to press button “WR/SEL”.

5.2.6 Mode of Advanced User Level

Access to the advanced user level

Press the “SETUP” button for 5 seconds, release the button.

If the level is password protected, the led “SETUP” is on and the display shows the PASSWORD inscription and “000” will flash (Figure 5.7).

Advanced user password

Figure 5.7 – Advanced user password

Using UP and DOWN buttons sequentially, enter the three-digit password of advanced user, from 1 to 9 and separate dialing with pressing the button “WR/SEL”. If the password is wrong, then LCD will display “ERROR” and after 15 seconds UBZ-305M will return to the view state of the parameters, otherwise UBZ will go to the advanced user level (Figure 5.8).

Figure 5.8 – Advanced user level

The procedure for changing the settings on the advanced user level is the same as user-level (section 5.2.5), but the parameter recording does not depend on the inscription “ADV” presence in the fourth line of the indicator. However, to change the value of the parameter, the parameter should be included in the list of MNS.

At the advanced user level the availability of any parameter at the user level can be disabled or enabled. To do this:

using DOWN and UP buttons, select the parameter (Figure 5.8)
enter the menu where setting is changed by pressing “SETUP” button
press both buttons “SETUP” and DOWN

In case of restricting access to change the parameter at the user level in the fourth line of the indicator the inscription “ADV” will display.

5.2.7 Factory Settings

Factory settings are possible in two ways.

First method: set the parameter “Default Factor” to “On”. After exiting from the mode for setting the factory settings will be restored.

This method does not recover the following settings:

access code of advanced user (“Password”)
current time and date
clock correction (“Correct Time”)
the unit operating time (“Time UBZ-305M”)
operating time of the motor (“Time motor”)

Second method: when UBZ-305M energizing, hold pressed for two seconds the buttons “SETUP” and “WR/SEL”. Factory settings are restored (advanced user password - 123).

This method does not recover the following settings:

the unit operating time (“Time UBZ-305M”)
operating time of the motor (“Time motor”)
clock correction (“Correct Time”)

After you complete the installation of factory parameters, UBZ-305M will start operation in the mode of MNS, the list of which the settings are included:

CT output current, “CT out i”
CT rated current, “CT nom i”
motor rated current, “Rated Inom”

5.2.8 Real Time Setting

To set the real time:

pressing “SETUP” button, enter the parameters setting mode
using UP and DOWN buttons, select parameter “Real Time”
press the button “SETUP” (Figure 5.9)

Time setting display

Figure 5.9 – View of the display when setting the time

using UP and DOWN buttons, select the desired date and press the button “WR/SEL”
repeat step 4 to set the month, year, hour and minute

When recording minutes (at the moment of pressing the button “WR/SEL”), the number of seconds will be automatically set to zero.

If you move to the next parameter without changes, instead of the button “WR/SEL”, press the button “SETUP”.

If no button is pressed for 15 seconds, UBZ-305M will automatically switch to the parameter view mode.

5.2.9 UBZ-305M Faults Reset on Front Panel

Fault reset is performed when the motor is off. To reset the faults on the front panel, press simultaneously the buttons “SETUP” and DOWN, in this case:

faults are reset regardless of whether ARS is disabled or enabled (besides the current faults and faults by the presence of motor currents when load relay is off)
counting of ARS is off
in the absence of the current troubles the motor is off

5.2.10 Energy Meters Reset

Reset of energy meters (total, active and reactive) is performed when setting the parameter “Energy RESET” to “On” (setting to “1” when using USB/RS-485 interface). After reset of energy meters, the parameter “Energy RESET” will automatically switch to “Off” (“0” – when reading the parameter via USB/RS-485 interface).

5.3 UBZ-305M Operation

In describing the operation of UBZ-305M it is assumed that this protection is enabled and all the required sensors are connected.

5.3.1 UBZ-305M Operation Before Load Relay On

5.3.1.1 UBZ-305M Operation After Energizing (First Start-up)

After energizing the indicator displays the device name, the version number of software, the name of the manufacturer and the operation performed (Figure 5.10).

Indicator view after energizing

Figure 5.10 – UBZ-305M indicator view after energizing

After 1-2 seconds the indicator will display the values of the measured parameters. What parameters will be displayed on the indicator it depends on the value of the parameter “Indicat <Start”:

line voltages at “Indicat <Start”=“LineU”
the motor operating time, the insulation resistance of the motor and mains frequency at “Indicat <Start”= “InsFr”

Before the load relay enabling UBZ-305M checks the following:

the level of stator winding insulation relative to the motor housing (when insulation resistance is less than 500 ± 20 kΩ at “Insulation Mr” = “5” (1000 ± 50 kΩ at “Insulation Mr” = “10”) the load is not enabled)
the quality of the mains voltage: full phase, symmetry, the current line voltage value
correct phase sequence, the lack of their “coincidence”

If any of disabling factors, the load relay is not activated, and the display of mnemonics shows the corresponding message about the fault (Table 5.13) and the led “FAULT” lights up.

In the absence of disabling factors, enabling the load relay is determined by the value of parameter “Start>Power” (UBZ-305M operation after energizing):

when “Start>Power” = “StOff”, the load relay will not be enabled. To enable the load relay in this case, you should simultaneously press UP and DOWN buttons.
when “Start>Power” = “St>AR” the load relay will be enabled after ARS time.
when “Start>Power” = “St>2s” the load relay will be enabled within 2 seconds after energizing.

Simultaneously with the load relay enabling the green led “Power relay” lights up.

After you activate the relay and up to the moment of the motor starting (motor start is determined by the excess of the load current of 120% level of rated current), control and taking action on voltage quality is maintained. If within no-current pause the disabling factors are appeared, the load relay is deactivated.

UBZ-305M operation when enabled remote control of the motor via USB/RS-485 interface (parameter “MotorOp RS-2/5”) is considered in section 5.4.9.

5.3.1.2 UBZ-305M Operation After Shutdown Owing to the Fault

UBZ-305M operation in this case is similar to the work when first starting, but enabling the load relay does not depend on the value of the parameter “Start>Power”.

If after the fault ARS is disabled (“AR”=“Off”), then with disabled motor start on the front panel (it is determined by the value of the parameter “MotorOp UBZ-305M”) the automatic enabling the motor is impossible up to UBZ-305M turning off. The action of the parameter “AR” value is applied to all types of faults except voltage faults. To disable ARS in case of voltage faults you should use the parameters “Umax protec”, “Umin protec”, “Uimbal protec”.

5.3.2 UBZ-305M Operation After Load Relay Enabling and Motor Is On

UBZ-305M provides monitoring for voltage and currents. The load relay is disabled when any protection tripping from Table 5.13 with the exception of:

voltage protection
overcurrent protection with “Imax<>T” =“Ind” (in this case, the warning is there, but the load relay is not disabled)

The indicator can display phase currents of motor or group of three (two) parameters selected by the user (Table 3.5). The group of parameters selected by the user can be displayed constantly (“Indicat mode”=” Conti”) or for 15 s, and then indication of motor currents returns (“Indicat mode ” = “>15s”).

5.3.3 Functional Relay Operation

The functions performed by the functional relay are determined by the parameter “Relay F mode”.

When “Relay F mode” = “Alarm”, the relay is used as alarm relay (LEDs ”⚠” and “TR” do not on). The relay contacts are closed when there is any fault specified in Table 5.13.

When “Relay F mode” = “Timer”, the relay is used as time relay (LED “TR” is on): it turns on after the time set by the parameter “Relay F time”, after the load relay enabling.

When “Relay F mode” = “St->D”, the relay is used to switch the motor windings from star to delta (LED ”⚠” is on). In this mode the load relay is activated the same way as in the mode “Alarm”, but after the time set by parameter “Relay F time” it is disabled. After the time set by the parameter “Delay RP RF”, after the load relay is off, the functional relay is activated.

5.4 Operation of UBZ-305M Together with Computer

5.4.1 Communication Protocol and Interface

The communication between UBZ-305M and computer can be via USB or RS-485 interface (parameter “Communication”).

For communication MODBUS Protocol is used in RTU mode or MODBUS in ASCII mode (parameter “ASCII-RTU”).

In ASCII mode 8-bit data is the combination of two ASCII characters (Table 5.2). For example, 1–data byte: 64 Hex, in ASCII consists of two characters ‘6’ (36 Hex) and ‘4’ (34 Hex).

Table 5.2 – ASCII characters

Character	’0'	'1'	'2'	'3'	'4'	'5'	'6'	'7’
ASCII code	30 Hex	31 Hex	32 Hex	33 Hex	34 Hex	35 Hex	36 Hex	37 Hex

Character	’8'	'9'	'A'	'B'	'C'	'D'	'E'	'F’
ASCII code	38 Hex	39 Hex	41 Hex	42 Hex	43 Hex	44 Hex	45 Hex	46 Hex

In RTU mode 8-bit data is the combination of 4-bit hexadecimal digits. For example, 64 Hex.

During data exchange via RS-485 or USB the blue LED “RS-485” is on.

Each UBZ-305M has the individual communication address. The computer controls each UBZ-305M recognizing them by their addresses.

5.4.2 Communication Parameters

the unit address: 1-247 (parameter “Address UBZ-305M”)
data transfer rate: 9600 baud, 19200 baud (parameter “Data speed”)
reaction to loss of connection: the continuation of operation with no warning, the warning and continued operation, the warning and stopping the motor with ARS enabling after restoration of communication, warning and motor stop with ARS disabling (parameter “Loss connect”)
detection of exceeded time for reply: 1s – 120s (parameter “Overexceeding”)

The format of the transmitted word is the following:

8 data bits in RTU mode and 7 data bits in ASCII mode
parity check (parameter “Even parity”): disabled (“Off”), enabled (“On”); (factory setting is “Off”)
number of stop bits (parameter “Stop bit”): 1 or 2 (factory setting is 2)

5.4.3 Communication Protocol

Exchange between PC and UBZ-305M is carried by data packets. Data packet format in RTU mode is shown in Table 5.3 and in ASCII mode – in Table 5.4.

Table 5.3 – Data packet in RTU mode

Name	Description
START	Silence interval – over 4 ms at transmission rate of 9600 baud, or more 2 ms at 19200 baud
ADR	UBZ-305M communication address (8 bit)
CMD	Command code 8 bit
DATA 0…n-1	Content of data: N*8 bit data (n<=24)
CRC CHK low	CRC – Cyclic Redundant Check, 16 bit
CRC CHK high
END	Silence interval – over 4 ms at transmission rate of 9600 baud, or more 2 ms at 19200 baud

Table 5.4 – Data packet in ASCII mode

Name	Description
STX	Start character ’:’ (3A Hex)
ADR1, ADR0	UBZ-305M communication address (8 bit) consisting of two ASCII chars
CMD1, CMD0	Command code 8 bit consisting of two ASCII characters
DATA 0…n-1	Content of data: N*8 bit data (n<=24) consisting of two ASCII chars
LRC CHK 1, 0	LRC Cyclic Redundant Check: 8-bit control total as two ASCII chars
END1	End of characters: END1= 0D Hex – carriage return (CR)
END0	END0 = 0A Hex – line feed (LF)

5.4.4 Command Codes

5.4.4.1 General

The format of data characters depends on command codes. Examples of transmission of commands and data are given for RTU mode. For ASCII mode the command codes are not changed, but the format of the transmission data and control of data is based on the Table 5.4.

5.4.4.2 Command for Reading the Register Group

Command code – 0x03, reading n-words

For example, reading of continuous 2 words from starting address 2102H in UBZ-305M with communication address 01H in RTU mode (Table 5.5) and in ASCII mode (Table 5.6).

Table 5.5 – Command for reading registers (RTU mode)

Command message		Response message
ADR	0x01	ADR	0x01
CMD	0x03	CMD	0x03
Start address of data	0x21	Number of data in bytes	0x04
	0x02
Number of data in words	0x00	Content of data at address	0x17
	0x02		0x70
CRC CHK low	0x6F	Content of data at address	0x00
			0x00
CRC CHK high	0xF7	CRC CHK low	0xFE
		CRC CHK high	0x5C

Table 5.6 – Command for reading registers (ASCII mode)

Command message		Code transferred, HEX	Numbers for LRC, HEX
STX	’:‘	3A
ADR	’0’	30	01
	’1’	31
CMD	’0’	30	03
	’3’	33
Start address	’2’	32	21
	’1’	31	02
	’0’	30
	’2’	32
Number of words	’0’	30	00
	’0’	30	02
	’0’	30
	’2’	32
LRC CHK 1	’D’	44
LRC CHK 0	’6’	36
END1	CR	0D
END0	LF	0A

5.4.4.3 Command of Register Entries

Command code – 0x06, record – one word

Data recording is possible at the addresses of programmable parameters (Table 3.6), except the parameters listed in Table 5.7.

The parameter recording is independent of set protection of the advanced user (entry by the communication line has higher priority).

When recording new value of the parameter into the cell protected by MNS, the parameter is automatically removed from this mode.

Table 5.7 – Parameters not available for recording via MODBUS

Settings and readings	Displaying	Address
Total time of the unit operation	Time UBZ	217
Motor operating time, day	Time motor	218
Access code of user	Users code	219
Access code of advanced user	Password	220
Restoration of factory settings	Default Factor	221
The unit design version	Version	230

Example: recording order is 1000 (0x03E8) to register with address 0x00A0 to UBZ-305M with communication address 01H in RTU mode is shown in Table 5.8.

Table 5.8 – Command for writing register (RTU mode)

Command message		Response message
ADR	0x01	ADR	0x01
CMD	0x06	CMD	0x06
Start address of data	0x00	Start address of data	0x00
	0xA0		0xA0
Data	0x03	Data	0x03
	0xE8		0xE8
CRC CHK low	0x89	CRC CHK low	0x89
CRC CHK high	0x56	CRC CHK high	0x56

5.4.4.4 Command for Diagnostics

Command code 08h – diagnostics

The 08h function provides a number of tests for checking the communication system between PC and UBZ-305M, and UBZ-305M serviceability control.

The function uses the sub-function field to specify the action performed (test).

Sub-function 00h - return of request data

The data transmitted in the data field of the request should be returned in the response data field.

Example of request and response for MODBUS RTU mode:

Request:

Address	Function	Sub-function HB	Sub-function LB	Data HB	Data LB	CRC LB	CRC HB
01h	08h	00h	00h	A0h	3Ch	98h	1Ah

Response:

Address	Function	Sub-function HB	Sub-function LB	Data HB	Data LB	CRC LB	CRC HB
01h	08h	00h	00h	A0h	3Ch	98h	1Ah

Sub-function 01h – restart of communication options

During fulfillment of the command UBZ-305M performs only change in baud rate. To change totally the communication settings you should run the command “UBZ RESTART” (“RESTART”).

Example of request for MODBUS RTU mode:

Address	Function	Sub-function HB	Sub-function LB	Data HB	Data LB	CRC LB	CRC HB
01h	08h	00h	01h	00h	00h	B1h	CBh

Response is not returned.

5.4.5 Control of Correct Transmission of Data Packet

5.4.5.1 Control in RTU Mode

To check the correctness of data transmission in RTU mode the CRC Cyclic Redundant Check – the code for cyclic control is used.

The Cyclic Redundant Check (CRC16) is a cyclic verification code based on the polynomial A001h. The transmitting device forms the Cyclic Redundant Check for all bytes of the message transmitted. The receiving device similarly generates the Cyclic Redundant Check for all bytes of the message received and compares it with the Cyclic Redundant Check received from the transmitting device. In case of mismatching the generated and received Cyclic Redundant Check the error message will be generated.

The field of Cyclic Redundant Check has two bytes. CRC in the message is transferred with low byte first.

CRC is formed by the following algorithm:

loading CRC register (16 bit) by units (FFFFh)
exclusive OR with the first 8 bits of the byte of the message and CRC register contents
shift of the result one bit to the right
if shifted bit = 1, exclusive OR of the contents of the register with value A001h
if shifted bit = 0, repeat step 3
repeat steps 3, 4, 5, until 8 shifts
exclusive OR with the following 8 bits byte of the message and CRC register contents
repeat steps 3 to 7 until all bytes of the message will be processed
the final contents of the register will contain the CRC

Example of Program CRC code generation in the language C. The function has two arguments:

unsigned char* data – a pointer to the message buffer
unsigned char length – the quantity of bytes in the message buffer

The function returns the CRC value as a type of unsigned integer.

unsigned int crc_chk(unsigned char* data, unsigned char length)
{
    int j;
    unsigned int reg_crc=0xFFFF;
    while(length--)
    {
        reg_crc ^= *data++;
        for(j=0;j<8;j++)
        {
            if(reg_crc & 0x01)
                reg_crc=(reg_crc>>1) ^ 0xA001; // LSB(b0)=1
            else
                reg_crc=reg_crc>>1;
        }
    }
    return reg_crc;
}

5.4.5.2 Control in ASCII Mode

To check the correctness of data transfer in ASCII mode LRC Redundant Check – longitudinal redundancy check. CRC is 8-bit number transmitted as two ASCII characters. The CRC is formed by inverse transformation of all ASCII characters in eight-bit binary number, the addition of these numbers without accounting for the transfer, and the calculation of additional code of the received number. At the receiver, the LRC is calculated again and compared with the received LRC. In the calculation of LRC the colon, CR and LF are discarded.

5.4.6 Register Addresses

The register addresses of measured and calculated parameters of UBZ-305M are given in Table 3.5.

The register addresses of programmable parameters are given in Table 3.6.

The register addresses of special and service parameters and their purpose are given in Table 3.4.

The register address of the status and purpose bit data in Table 5.9.

The register addresses of the alarm log are given in Table 5.9.

The register addresses of time settings are given in Table 5.10.

The register address of commands is 903 (Table 5.12).

Table 5.9 – Register addresses and bit definitions

Description	Address	Service	Remark
Register of UBZ-305M state	900	Bit 0: 0 – No fault; 1 – fault (code of fault in register 241)
		Bit 1: 0 – load relay is disabled; 1 – load relay is enabled
		Bit 2: 0 – functional relay is disabled; 1 – functional relay is enabled
		Bit 3: 0 – restart is disabled; 1 – ARS is waited
		Bit 5-4: Mode of functional relay: 00 – alarm relay; 01 – time relay; 10 – star/delta
		Bit 6: 0 – MNS mode is disabled; 1 – MNS mode is enabled
		Bit 7: 0 – clock battery is normal; 1 – the clock battery should be replaced
		Bit 8: 0 – not in hysteresis area; 1 – in hysteresis area when operating with analog inputs
Register of fault 1	901	Bit service as per Table 5.13	0 – no fault; 1 – fault
Register of fault 2	902	Bit service as per Table 5.13	0 – no fault; 1 – fault
Fault logbook
Fault code 1	1000	Fault code as per Table 5.13
Parameter value 1	1001	Parameter value as per Table 5.13
Fault time 1	1002	Low byte – seconds, high byte – minutes
	1003	Low byte – hours, high byte – day of month
	1004	Low byte – month, high byte – (year minus 2000)
Fault code N	1000+(N-1)*5	Fault code as per Table 5.13
Parameter value N	1000+(N-1)*5+1	Parameter value as per Table 5.13
Fault time N	1000+(N-1)*5+2	Low byte – seconds, high byte – minutes
	1000+(N-1)*5+3	Low byte – hours, high byte – day of month
	1000+(N-1)*5+4	Low byte – month, high byte – (year minus 2000)

5.4.7 Time Parameter Registers

The parameters are transmitted in binary decimal code. For example, the code 0x14 in the register of minutes means 14 minutes.

Registers of time settings allow reading and recording of data.

Table 5.10 – Register addresses for time settings

Parameter	Address	Remark
Seconds	80
Minutes	81
Hours	82
Day	83
Month	84
Year	85	Last two digits of the current century are recorded (read)

5.4.8 Communication Errors Handling

In case of erroneous situation when making the frame (parity error, frame error, checksum error) UBZ-305M returns no reply.

In the event of an error in the format or value of data transferred (unsupported function code, etc.) UBZ-305M accepts the request frame and builds a response with a symptom and error code. The error indicator is the high bit set to one in the function field. For the error code there is separate field in the response.

Example – Request (Function 30h is not maintained):

Address	Function	Data	CRC LB	CRC HB
01h	30h		XXh	XXh

Response:

Address	Function	Error code	CRC LB	CRC HB
01h	B0h	01h	94h	00h

Table 5.11 – Error codes

Error code	Name	Description
01h	ILLEGAL FUNCTION	Received function code cannot be processed by UBZ-305M
02h	ILLEGAL DATA ADDRESS	The data address specified in the request is not available to this slave
03h	ILLEGAL DATA VALUE	The value contained in the request data field is disabled value for UBZ-305M
04h	SLAVE DEVICE FAILURE	While UBZ-305M attempted to perform the requested action, unrecoverable error occurred
05h	ACKNOWLEDGE	UBZ-305M accepted the request and is processing it, but this takes much time
06h	SLAVE DEVICE BUSY	UBZ-305M is busy of processing a command. The master should repeat the message later
07h	NEGATIVE ACKNOWLEDGE	UBZ-305M cannot perform the program function received in request

5.4.9 Remote Control of the Motor Using USB/RS-485 Interface

UBZ-305M operation in remote control mode is determined by parameter “MotorOp RS-2/5”:

When “MotorOp RS-2/5” equal to “Off” (0) – remote control of the motor is disabled.

With activated remote control (parameter “MotorOp RS-2/5” equal to “OnSta”(1) or “OffSta” (2)), motor start on the front panel is disabled regardless of the value of the parameters “MotorOpUBZ” and “Start>power”.

When “MotorOp RS-2/5” equal to “OnSta” – after energizing UBZ-305M operates in the same way as when the remote control is disabled (normal device operation), but it is enabled to record to the command register R_COMMAND. Automatic motor start is possible only after ARS time.
When “MotorOp RS-2/5” equal to “OffSta” – UBZ-305M will start the motor only after the receipt of the respective command via USB/RS-485 interface.

The value R_COMMAND is taken into account by UBZ-305M operation algorithm when “MotorOp RS-2/5” =“OnSta” and “MotorOp RS-2/5” = “OffSta”. If “MotorOp RS-2/5” = “Off” and the user sets “MotorOp RS-2/5” “OnSta” or “MotorOp RS-2/5” = “OffSta”, then in R_COMMAND zero (0) will be recorded.

The list of possible register setup of commands is shown in Table 5.12.

When “MotorOp RS-2/5” = “OnSta”, then after energizing in the command register 1 is recorded (normal device operation).

When “MotorOp RS-2/5” = “OffSta”, then after energizing in the command register 0 is recorded (motor is disabled prior to entering the command to enable).

In case of emergency shutdown of the motor by simultaneously pressing DOWN, UP (when “MotorOp UBZ” = 2 (“Stop”) or “MotorOp UBZ” = 3 (“St<>”)), 0 will be reset in the command register.

Table 5.12 – Values of command register

Command register R_COMMAND (Address = 903)	Action fulfilled
0	Turn off the motor. If the motor is turned off, before receiving a command from the remote control to turn on the motor will not turn on. If the motor is on, the motor will be off.
1	Normal operation of the device. If the motor has been disabled by the command of the remote control or by simultaneous pressing DOWN, UP when “MotorOp UBZ” = 3 (“St<>”) or when fault occurs, after which ARS is possible, then enabling the motor when 1 record to R_COMMAND will happen after ARS time from the moment the motor is turned off.
2	The early motor switching on. Record 2 turns on the motor before the ARS time finishes. After the motor enabling R_COMMAND =1.
55 (37 Hex)	Command “FAULT RESET” (section 5.4.10)
88 (58 Hex)	Command “UBZ RESTART” (“RESTART”) (section 5.4.11)

5.4.10 Command “FAULT RESET”

Command “FAULT RESET” is fulfilled after recording the command code 55 in the command register (Table 5.12) via USB/RS-485 interface.

When the command is fulfilled:

all faults are reset (whether ARS is disabled or enabled)
ARS count ends
if there is no current fault, the motor is enabled

5.4.11 Command “UBZ RESTART” (“RESTART”)

Command “UBZ RESTART” is used for entering into effect of the changed parameters of communication.

Command “UBZ RESTART” is fulfilled after record of command code 88 in the command register (Table 5.12) via USB/RS-485 interface. After receiving Command “UBZ RESTART”, UBZ-305M does not return confirmation of received command.

5.4.12 UBZ-305M Factory Settings Using MODBUS Interface

To do this, you need to set the parameter “Default Factor” = 1. In this case the operation parameters of the serial interface will not change (reset of interface settings to factory settings is not performed). The execution time of reset to the factory setting is to 5 seconds. After the operation finished the parameter “Default Factor”=0.

5.5 Emergency Conditions System

In case of emergency state of UBZ-305M:

in the fourth line of the indicator the alarm message displays (Figure 5.14) (fault code corresponds to Table 5.13)
red LED “FAULT” is on (with constant light if ARS is disabled and with flashing, if ARS is expected)
the load relay is disabled
functional relay is activated (when “Relay F Mode” = “Alarm”)

UBZ-305M indicator in fault mode

Figure 5.14 – UBZ-305M Indicator in mode of view for measured and calculated parameters (if there is a fault)

If UBZ-305M defines several different types of faults at the same time, the codes of faults and parameter values are displayed sequentially, one by one (on the indicator the number of displayed fault is changed).

If ARS is enabled, then in the fourth line of the indicator alternately the codes of faults and the time in seconds remaining until ARS are shown (Figure 5.15) (if the waiting time for thermal overload of the motor is more than the ARS time, then the waiting time is displayed). If ARS is disabled, the state of ARS in the third line is not displayed.

Indicator showing ARS countdown

Figure 5.15 – Indicator when displaying the time remaining until ARS

Table 5.13 – Fault codes

Fault description	Fault mnemonics	Parameter value	Register address of parameter value	Fault code	Register address of faults for N bit
Maximum phase current	I max	Maximum phase current	300	0	901:0
Thermal overload	Thermal over		301	1	901:1
Ground fault (zero sequence current)	Iearth	Zero sequence current	302	2	901:2
Excess ratio of negative sequence current to negative sequence voltage	Coef I/U	Coefficient × 100	303	3	901:3
Negative sequence current	I2 rev	Negative sequence current	304	4	901:4
Minimum phase current	I min		305	5	901:5
Delayed start	LongStart	Current	306	6	901:6
Rotor blocking	Block Rot	Current	307	7	901:7
Upon reaching the temperature threshold of the first transmitter	Temp1	Temperature in degrees	308	8	901:8
Upon reaching the temperature threshold of the second transmitter	Temp2	Temperature in degrees	309	9	901:9
Phase sequence	PhaseSequen		310	10	901:10
External MS (presence of currents when load relay is disabled)	Contactor	Current	311	11	901:11
At minimum line voltage	U min	Voltage	312	12	901:12
At maximum line voltage	U max	Voltage	313	13	901:13
At phase imbalance	Uimbal	Imbalance	314	14	901:14
Minimum insulation resistance of motor winding	Insul Res	Insulation resistance	315	15	901:15
Mains minimum frequency	F min	Frequency	316	16	902:0
Mains maximum frequency	F max	Frequency	317	17	902:1
Fault of remote control channel	RemoteCont			18	902:2
Motor emergency shutdown without possibility for restart	Stop nAR			19	902:3
Motor emergency shutdown with possibility to restart by pressing UP+DOWN	Stop Motor			20	902:4
S.c. of temperature transmitter 1	ShortTempS1			21	902:5
Breakout of temperature transmitter 1	BreakTempS1			22	902:6
S.c. of temperature transmitter 2	ShortTempS2			23	902:7
Breakout of temperature transmitter 2	BreakTempS2			24	902:8
Loss of phase	Break Phase			25	902:9
EEPROM destruction	Error EEPROM			26	902:10
At analog input “0-20 mA”	Input I		327	27	902:11
At analog input “0-10 V”	Input U		328	28	902:12
Improper calibration	Error CALIB			29	902:13

Notes:

Occurrence of fault as “EEPROM Error” – the destruction of EEPROM indicates that the data of the programmed parameters (Table 3.6) is damaged. To continue the operation, it is necessary to turn off UBZ-305M and restore the factory settings (section 5.2.7 – second method).
Occurrence of fault as “Error CALIB” – UBZ-305M improper calibration means that the calibration coefficients of the measured data are damaged. The continued operation of UBZ-305M is impossible. Re-calibration of the device is required to be done at the manufacturer factory.

5.6 Emergency Conditions Logbook

When disabling the load relay in the event of fault, UBZ-305M records in its memory the code of the fault, the value of the parameter on which the fault occurred and time of occurrence.

Number of simultaneously stored fault codes is 50. In case of subsequent faults occur, the fault information is recorded in place of the oldest fault.

To view the log, it is necessary to press button “WR/SEL”.

LED “SETUP” will on in flashing mode, and UBZ-305M indicators will display the latest fault (Figure 5.16).

Fault logbook display

Line 1 – indication of mode (alarm logbook)
Line 2 – number of the fault (1 – means the most recent fault)
Line 3 – mnemonic of the fault as per Table 5.13 and the parameter value at the moment of the fault occurrence
Line 4 – time and date of the fault

Figure 5.16 – Display in the view mode of the fault logbook

View the fault logbook by pressing the UP or DOWN button.

To exit the view log mode, press the button “WR/SEL” or exit will be automatically in 30 seconds after the last pressing of any button.

5.7 Motor Control on UBZ-305M Front Panel

Depending on the value of the parameter “MotorOp UBZ”, you can control the load relay of UBZ-305M by simultaneously pressing the UP and DOWN buttons:

“Off” – no reaction
“Start” (motor start is enabled) – the load relay will be enabled if ARS time has not finished
“Stop” (motor emergency shutdown) – the load relay will be disabled with the issuance of fault code “Stop nAR”. The restart of the motor is possible only after de-energizing and re-energizing of UBZ-305M unit
“St<>” (motor start and shutdown is permitted) – the load relay is disabled with issuance of code “Stop Motor”. To enable it, press again UP and DOWN buttons

5.8 Motor Control Using Analog Inputs

The motor control algorithms by the analog inputs “0-20 mA” and “0-10 V” are shown in Table 3.6.

After the motor stopping according to emergency level the countdown for ARS will only start after going out the parameter value of the emergency zone.

If after the motor switching off by the alarm level the parameter value is between the levels on and off for the motor, then:

indicator “Motor” blinks
indicator “FAULT” is off
the fault code is displayed on LCD

6. Maintenance

6.1 Safety Precautions

Maintenance of the unit should be performed by persons admitted to the operation and have the appropriate permission. The recommended frequency of maintenance is every six months.

6.2 Maintenance Procedure

Check the wires connection reliability, if necessary – clamp with force as specified in Table 3.1
Check visually the housing integrity
If necessary, wipe with cloth the front panel and the unit housing

7. Transportation and Storage

UBZ-305M in the original package of the Manufacturer should be stored indoors with temperature from minus 45 to +60°C and relative humidity of not more than 80% in the absence of vapors harmfully acting on the packaging and materials of the device.

During transportation of UBZ-305M, the consumer should protect the unit from mechanical damage.

8. Service Life, Shelf Life and Manufacturer Warranty

8.1 The unit service life is 10 years. Upon expiration of the service life you should contact the Manufacturer.

8.2 Shelf life is 3 years.

8.3 Warranty period of the unit operation is 5 years from the date of sale.

During the warranty period the Manufacturer is responsible for free repair of the unit, if the Consumer has complied with the requirements of this Operation Manual.

8.4 Warranty service is performed at the place of purchase or by the Manufacturer of the Unit.

8.5 Post-warranty service is performed by the Manufacturer at current rates.

8.6 Before sending for repair, the unit should be packed in the original or other packaging excluding mechanical damage.

For all questions, please contact the Manufacturer:

“Novatek-Electro” Ltd.

Website: www.novatek-electro.com
Address: 59, Mykhailo Boltenko (Admiral Lazarev) str., Odesa, Ukraine, 65007
Tel: +38 (067) 565 37 68; +38 (050) 359 39 11; +38 (063) 301 30 40

Novatek-Electro UBZ-305M Documentation
Appendix A: Current Protection Curves Current Protection with Dependent Time Delay Section titled “Current Protection with Dependent Time Delay”

Novatek-Electro UBZ-305M Documentation

Appendix B: Star-Delta Starting

UBZ-305M Operation for Motor Control with Winding Changeover When Star-to-Delta Starting

When UBZ-305M is in the star-delta mode it is allowed performing the motor control in the following ways:

the motor disabling/enabling using the external automatic starter (actuator) at the same time with the de-energizing/energizing the UBZ-305M
motor control on the front panel of UBZ-305M
motor control via USB/RS-485 interface

Connection Diagram

Legend:

К1 – Star starter of motor winding enabling
К2 – Delta starter of motor winding enabling
К3 – Starter of motor enabling
Q1, Q2, QF – Circuit breaker

Figure B – Diagram for UBZ-305M enabling for the motor operation with star-delta switching over and the motor insulation control

Novatek-Electro UBZ-305M Documentation

Novatek-Electro UBZ-305M Documentation

Table of Contents

Novatek-Electro UBZ-305M

Key Features

Protection Functions

Common Use Cases

Documentation

Technical Reference

Technical Specifications

Related Products

Support

UBZ-305M Operating Manual

Abbreviations and Terms

1. Application

1.1 General

1.2 Operating Conditions

1.3 Changes in the Characteristics and Operation of UBZ-305M Depending on Program Version

1.4 Controls and Overall Dimensions

1.4.1 Design

1.4.2 Indication and Controls

2. Components

3. Specifications

3.1 Basic Technical Specifications

3.2 Measured, Calculated, Special and Service Parameters

Currents

Voltage

Miscellaneous

3.3 Programmable Parameters

Real Time Setting

Transformers

Basic Parameters

Over-current Protection

Ground Fault Protection (for zero-sequence current – I earth)

Negative-sequence Current Protection

Analysis of Causes for Negative Sequence Current Tripping

Thermal Overload (Heat Model of the Motor)

Minimum Phase Current

Delayed Start, Rotor Blocking

Voltage Protection

Motor Phase Loss with Current Control

Frequency Protection

Motor Control and ARS

Temperature Control

Motor Insulation Resistance

Miscellaneous

Serial Interface Parameters (RS-485/USB)

Control via Analog Input 0-20 mA

Control via Analog Input 0-10 V

3.4 Protection Functions

3.4.1 Protection Types

3.4.2 Maximum Phase Current Protection

3.4.3 Ground Fault Protection

3.4.4 Negative-sequence Current Protection (Imbalance)

3.4.5 Minimum Phase Current Protection

3.4.6 Delayed Start and Rotor Blocking

3.4.7 Thermal Overload Protection

3.4.8 Windings Overheating Protection

3.4.9 Voltage Protection

3.4.10 Phase Sequence Protection

3.4.11 Network Power Frequency Drop Protection

3.4.12 Network Power Frequency Rise Protection

3.4.13 Protection for Minimum Resistance of Motor Winding Insulation

3.4.14 Protection for Motor Phase Break (Loss)

3.4.15 Serviceability Check of External Magnetic Starter

4. UBZ-305M Design

5. Intended Use

5.1 Preparation for Operation

5.1.1 Preparation for Connection

5.1.2 Selection of Current Transformers (CT)

5.1.3 General

5.1.4 UBZ-305M Connection

5.2 UBZ-305M Control

5.2.1 Modes of UBZ-305M Control and Status

5.2.2 Measured and Calculated Parameters View State

5.2.3 Mode of Keyboard Blocking

5.2.4 Mode of Minimum Number of Settings (MNS)

5.2.5 Mode of User Level

5.2.6 Mode of Advanced User Level

5.2.7 Factory Settings