The FLEXeCHARGE Gateway Connect has an integrated Modbus TCP Server, which allows to dynamically change the maximum cluster current during runtime, and read back the currently allocated maximum cluster current, which has been set by the load management engine.
Modbus-TCP is an industry standard protocol, that can be used to interface third party equipment with the FLEXeCHARGE Gateway Connect.
By default, for IT security reasons, the Modbus TCP service is disabled. To enable it, please send a request to your local FLEXeCHARGE support team, which will enable the Modbus TCP service for you.
The Modbus dynamic cluster limit register is an unsigned 16 bit register, which can be set using Modbus Function Code 6 writing a Single Holding Register. The UnitID is 255 and the register address is 0x0.
The load management engine operates internally with a hard configured maximum cluster limit and a dynamic cluster limit, which can chang eduring runtime:
The load management engine will in particular situations reduce/overwrite the dynamic cluster limit. This is, for example, the case if the Unbalanced Load Preventation is active and the cluster limit needs to reduced to prevent unbalanced phase load. In this case if a greater dynamic cluster limit is being set via Modbus, the lower limit set by the load management engine will not be exceeded. If the phase unbalance is resolved, the system will use the latest value being set in the Modbus register as the cluster limit.
Setting a dynamic cluster current of 0A will suspend all charging and ensures, that no charge current is allocated.