I am looking at installing a multiplus II 10000VA with 2 X multiplus 5000VA as backup in an offgrid system. The idee is that if the large unit fails the 2 older units take over. But I want to turn on the 2X 5kw only if the big unit fails as it would be such a waste of energy to have them all running (in standby) continuously. Any tips how to configure this? btw I run now 2 X 5kw multiplus with ccgx, AC and DC solar chargers, 64kW battery & JK smart bms
In this case, I would use external transfer switches for the AC out and AC in connections, it may be possible to wire both AC in and AC out on a 4 pole switch.
If turn of ac-in and ac-out with a transfer switch, the multiplus will run if it is turned on; from the battery, so this not seems to be solution. An ATS combined with a trigger to boot the backup units might work. But I am not sure how to do this.