I have a multiplus-II 48 which is currently operating as a backup for when grid fails, it is in a house.
The mains is split at an ATS-Automatic transfer switch, the multiplus-II is installed at a remote shed.
When mains fails the ATS switches to the multiplus-II but with a 16A limit, in normal operation the house load does not go through the multiplus-II because it is limited to 16A and 40A is peak load. In backup mode (mains has failed) the power to the remote location is off the house is on.
I am looking at adding PV via the 250/60 MPPT in to the multiplus-II.
I plan to modify the ATS to provide unswitched power at all times to the remote location, Install venus/colour gx at the remote position and AC monitoring at the origin (60m apart)
Q1, Can I use cat5/6/7 for comms between the GX & AC sensor with the victron usb adaptor at the GX
Q2, Given in standard operation the loads do not go through the multiplus-II at all will it just backfeed PV & Battery capacity to the local grid up to 16A? (The AC 1 & 2 outputs are basically disconnected in standard operation hence forward feeding is not possible)
Q3, Can I get standard RS232 (not TTL) out of the GX?
Q4, How do I prevent back-feeding on mains fail? I fear the main contactor will stay energised as it will sense the voltage from the Multiplus-II which in turn will prevent switch over to backup.