Hi, will I need the “current sensor” stated in the MPII spec sheet? I’d like to know if I can integrate, (two) MultiPlus II, the Ekrano GX, (eight), 610W solar panels, a 250Ah lithium energy storage system and a 14kWp Generac generator with its own ATS (RXSC 100A 1F), in a 2-phase 220V, public utility installation.
The idea is to have the electrical public utility as the first source of electricity, at the moment of a blackout, the ESS/Battery Bank engage as the second source of electricity, and when the batteries are at a very low level, and the electrical public utility is still without service, the generator would then engage, via its own ATS.
first thought is to upgrade the inverters to the Quatro -this has 2 AC inputs, one for grid, one for Gen. This will give you more control over when the gen starts if the mains fails. With ESS, AMF / ATS controllers for the generator are not needed - and will, unless overridden start the generator whenever mains fails, rather than putting the load on the battery as a priority.
1st, the MP2 has 1 AC in, and 2 AC out.
Also, on a large scale, it was cheaper to upgrade the central inverter/storage system than to add the distributed storage.
So, if you want to go down this path: The grid forming unit must be the largest inverter. This is the one that would connect to the mains or generator. Satellite units connect to the central inverter’s AC out 1, with their AC in 1. The satellite loads are connected to the respective AC out1 of the satellite inverters. These operate in ESS mode, with a node red flow (e.g.) setting the import/export power levels. These flows MUST obtain their command data from the central unit over a secure connection.
If you use Quatros, then the satellite units can also support a generator connection.
Use of an ATS on the satellite units will fragment the system, and possibly cause syncronisation issues when switching. This is avoided with the Quatro.