Modbus Meter – For Zero Export from SolarEdge
SolarEdge Modbus Meter primarily helps in limiting the export of power to the grid generated using solar power plant enabling it for zero export. It also helps in finding the generation of the solar power plant, export to the utility grid, import from the utility grid and full time consumption inside the house
It particularly is useful for large scale installations like schools, hospitals, industries and commercial buildings where the major loads are during the day time.
Procedure to avail a net meter takes anywhere between 4 weeks to 30 weeks. Having modbus meter helps in consuming the power generated from solar rooftop system from the minute of commissioning it. This takes care of all the day time loads till the bidirectional meter is availed.
This data is available in the remote monitoring app of SolarEdge giving us an understanding of generation from the system and consumption of the building as shown in the figure below.
Red colored graph in the above figure shows the loads of the building during the 24 hours. Blue graph indicates the generation and consumption in the building based on the total connected loads in the building.
It is in align with the total consumption. Total electrical load connected in the building is greater than the installed capacity of solar, that is why the generation most of the time is less than the consumption.
Advantages of having Modbus Meter
In case of the system not having a bidirectional meter
- Limits the export of solar power by generating what is required for building’s self consumption
- Continues to generate power based on the maximum and minimum energy needs of the building
- Can study the connected loads in the building all the times
- Can be used from the day of commissioning of the system till the bidirectional meter is installed
- This feature is highly useful for the buildings with high day time loads – Institutes, Hospitals, Commerical and Industrial buildings
- Remotely available monitoring data
In case of the system having a bidirectional meter,
- Electrical loads can be seen on a real time basis through out the day and night
- Peak time non-essential loads could be shifted to non-peak hours
- Remotely available monitoring data within the SolarEdge app
- Avoids loss of power generation
- It also can be used during the export limitations
- This meter holds the data of import, export and the connected loads which can also be seen in the monitoring portal
Working of the SolarEdge Modbus Meter
Export and Import data is read by a current transformer which is connected parallelly with the Electricity Board power supply to the SolarEdge Modbus meter through the communication cable, Modbus meter is connected to a SolarEdge Inverter.
Power optimizers are connected to Inverter through Power Line Communication (PLC) ensuring the monitoring data to be available in Modbus meter and the monitoring portal.
This could be used in single and three-phase systems as well.
When ordering a Modbus meter it is also necessary to consider ordering the Current Transformer.
|Current Transformer ER Model||Rated RMS Current (A)||Internal (A X B)
External (C X D)
|SE-ACT-0750-250||250||20 x 20 mm/61 x 60.4 mm|
|SE-CTS-2000-1000||1000||50.8 x 50.8 mm/121 x 127 mm|
More details on Installation of the Modbus meter: SolarEdge