Novatek-Electro UBZ-305M
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
Section titled “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
Section titled “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
Section titled “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
Section titled “Documentation”- Operating Manual – Complete operating instructions, installation, and configuration
Technical Reference
Section titled “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
Section titled “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 |
Related Products
Section titled “Related Products”- UBZ-304 – Similar motor protection unit with RS-232 interface
- UBZ-302M – Compact motor protection device
Support
Section titled “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