Add parameters

Parameters are the values HMI reads from and writes to equipment. Dashboards, reports, and automations all work with parameters, so a device shows up in them only after its parameters exist. You need the Editor, Admin, or Owner role and an endpoint the device is reached through; see Configure endpoints.

Apply a parameter template

A parameter template holds the whole parameter tree of one device model: names, units, registers, value types, and scaling. Applying it is the quickest way to add a supported device.

1. Open Setup → Parameters.
2. Select Add, then From template….
3. Under Template, choose the device model. Overvis templates are listed under Overvis, your workspace’s own templates under This workspace.
4. Choose the Endpoint the device is reached through.
5. Enter the device’s Unit ID. Several devices behind one gateway or MC252 share its endpoint and differ by unit ID.
6. Optionally change the Root branch name, for example to the device’s location.
7. Select Add.

The parameters are added in a new root branch. Keep the parameters you need. Before you delete unused ones, check that no dashboard or report uses them.

If no template fits your device, ask the assistant: it can build the parameters from the device’s manual. To write a template for a model you use often, see Author a parameter template.

Let the assistant find devices on an MC252

When devices are wired to an MC252’s RS-485 bus, the assistant can find their unit IDs, identify their models, and apply the matching templates for you. Follow Find devices on an MC252 RS-485 bus.

Add a Modbus parameter by hand

Use this for a single value, or for a device without a template. You need the device’s register map from its manual.

1. Open Setup → Parameters. If there is no branch yet, select Add, then Root branch, and create one.
2. Select Add, then Parameter.
3. Under General, choose the Branch and enter the Name and Units.
4. Under Source, choose Modbus TCP as the Source kind, then the Endpoint, the device’s Unit ID, the Table, and the Addresses. Addresses start at 0: register 1 in a manual that counts from one is address 0.
5. Under Value, choose the Value type that matches how the device stores the value, and set the Multiplier if the device stores it scaled, for example in tenths.
6. To keep a history of the value for reports and trends, enter a Background reading period (seconds).
7. Select Create.

Every field and value type is described in Parameter sources and Value types.

Check the new parameters

1. In Setup → Parameters, select the new parameters and turn on Live.
2. Compare the values with the device’s display or a reading you trust.

If a value shows an error, check the unit ID, table, and addresses against the register map, and that the endpoint is Connected; see Troubleshooting.