Zero Export Device EFR4002IP

An energy flow relay is a device used to optimize the consumption of self-generated energy, also known as a "zero-export" system.

Energy flow relays, such as the EFR4002IP, monitor the current flow between the public power grid and the energy producer/consumer. The device can be conveniently managed via a built-in web server or directly on the control panel. The measured values are displayed on the device screen. When an object generates excess energy, it is often more cost-effective to consume it internally. This is especially beneficial when there is a significant difference between the price paid to the energy supplier and the price the supplier pays for energy fed into the grid. Many areas suitable for photovoltaic installations have not been fully utilized due to limitations in the amount of energy that can be delivered to the grid connection point.

In Germany, the new VDE-AR-N 4105:2018-11 standards allow this value to be exceeded up to 66.6% or more of the installed capacity, provided that the excess power is consumed locally rather than fed into the grid. The EFR4002IP can monitor this process, ensuring system stability. This device can also be used in "zero-export" systems where no energy can be fed into the grid. In such cases, the EFR4002IP acts as an energy flow direction sensor (EnFluRi). The EFR4002IP has been optimized for these functions and enables data exchange with the power generation system (PGS).

Functions

• Switching up to 3 receivers: the largest receiver
• 1-2-3 or a combination of 3 receivers (7 levels)
• Switching on and off points where receivers are switched on and off
• Delay in switching on and off receivers, minimum switch-on time
• Control of heat pumps (SG-ready), battery chargers, inverters

Features:

• Can be used in medium voltage applications. Connection of grounded medium voltage transducers and series-connected measuring devices
• Active power measurement 1- or 3-phase ± 99.99 MW
• 3 inputs for standard current transformers with secondary 1 or 5 A.
• Possibility of connecting a current transformer and setting the ratio.
• Energy meters (supply and consumption)
• 3 relay outputs
• 4 digital inputs Y1-Y4 for control signals, e.g., relay ON/OFF
• IP connection, integrated web server
• Values available via Modbus TCP, SunSpec (energy meter)
• Analog outputs as a measuring transducer and for stepless receiver regulation