This article describes how to integrate an existing PV system into the reev EMS. You will learn which hardware components are required and how to correctly position the energy meter.
Prerequisites
Before you begin with the PV integration, make sure the following prerequisites are met:
Dynamic Load Management (DLM) is activated for your site.
The basic installation according to the reev EMS – Installation Guide: Dynamic Load Management is completed.
Compatible measuring devices are available (see Hardware Compatibility Table).
Note: DLM must be activated so that the reev EMS can take various on-site energy sources into account when distributing charging loads across your charging infrastructure.
Required Hardware Components
Depending on your site setup, existing metering equipment can be reused. The prerequisite is that it meets the requirements from the Installation Guide: Dynamic Load Management and uses compatible measuring devices as listed in the Hardware Compatibility Table.
Note: Even though the reev EMS supports various types of energy meters, a Teltonika router is always required. It acts as an IoT gateway: it reads out the Modbus registers of the meter and securely transmits the data to the reev EMS backend.
Step-by-Step Guide: Meter Placement for PV Integration
In addition to the standard installation steps from the DLM manual, PV integration requires a specific metering configuration. Follow these steps:
Place the energy meter upstream – i.e. before the building consumption and before the PV system (at the grid connection point).
Make sure the meter can continuously measure both the building's energy demand and the PV generation.
Verify the correct wiring using the diagram below.
Tip: By positioning the meter at the grid connection point, the reev EMS can dynamically adjust charging sessions to the available PV surplus – without a direct connection to the PV inverter.
How PV Detection Works
The reev EMS does not measure PV generation separately. Instead, it calculates the PV surplus indirectly based on the readings from the energy meter at the grid connection point.
Note: Direct communication or a physical connection to the PV inverter is neither required nor supported. No direct PV measurement or control takes place.
Further Information
For a deeper insight into how the reev EMS uses the metering data and which features result from it, refer to the Feature Guide for PV Integration.
Troubleshooting
Problem | Possible Cause | Solution |
PV surplus is not detected | Meter is not placed at the grid connection point | Check meter position: it must be installed upstream of building consumption and PV system |
No data transmission to the backend | Teltonika router not correctly configured or offline | Check router connection and Modbus configuration |
Charging sessions do not respond to PV generation | DLM not activated | Check DLM activation in the reev EMS |
Frequently Asked Questions
Does the PV inverter need to be directly connected to the reev EMS?
No. The reev EMS does not require a direct connection to the PV inverter. The PV surplus is calculated indirectly via the energy meter at the grid connection point.
Which energy meters are compatible?
The reev EMS supports various energy meters that communicate via Modbus TCP. You can find a complete list in the Hardware Compatibility Table.
Can I use an already installed energy meter?
Yes, provided the meter meets the requirements from the installation manual and communicates via Modbus TCP.
Is the Teltonika router mandatory?
Yes. The Teltonika router is always required, as it acts as an IoT gateway that reads out the Modbus data from the meter and transmits it to the reev EMS backend.
Where can I find the Dynamic Load Management instructions?
You can find the complete DLM installation guide in the reev EMS – Installation Guide: Dynamic Load Management.