Connecting devices
Connecting a site takes three steps: tell SEMS how to reach the devices, add the devices, and group them into a system.
1. Channels
Under Settings, Channels you create a channel for each RS485 bus, with its serial settings, or for a Modbus TCP device, with its address and port. Devices on one RS485 bus need their own unit IDs.
2. Devices
On the Devices page, Find Modbus devices searches an RS485 bus or network for unit IDs 1 to 247, and can also try common baud rates and parities. The scan only reads, and devices on that bus pause briefly.
Each match is shown with its vendor, type and confidence. Verify it and stage it; when you activate it, SEMS creates the device with polling off so you can review it first.
You can also add a device by hand with its type, profile, channel and unit ID. For a battery unit or an inverter behind a plant controller, set Managed by to the parent device. Here you also enter limits such as maximum AC power, maximum backup power, maximum PV production and the battery's depth of discharge.
OCPP EV chargers are registered on the EV Charger page instead.
3. Systems
Under Settings, Systems you give each device its role. Every device belongs to one system, and most sites have just one.
| Role | What it does in the system |
|---|---|
| Battery Controller | Controls the battery inverter and reports battery power and state |
| Site Energy Inverter | Controls a site energy inverter and reports its energy flows |
| PV Inverter | Produces solar power and can receive PV control commands |
| PV Output Meter | Measures total solar production |
| Grid meter | Measures import and export at the grid connection |
| Consumption Meter | Measures site load |
| Battery | Reports storage data without acting as its controller |
| Controllable Load | A load that SEMS can adjust |
| Generic Meter | Keeps a meter in the system without adding it to a total |
Values not measured directly can be built on the Metering page.
Check before control
The Home page should now show sensible values for every device, with grid import and export pointing the right way. See Commissioning for the full checklist.