VE Direct 24/500 Inverter Starts By Itself

[CRuMbS (Colin Stone)]

I have an VE Direct 24/500 inverter in a vessel and I am using the remote with 2 switches wired in series. 1 switch is a straight forward on off switch, the other is the NC contacts of a relay whose coil is supplied by a MP 24/3000/70 inverter. So, 3000 on, NC contacts open and 500 switches off.

When I am motoring, the 3000 is switched on and the 500 switches off as expected as the remote circuit is broken. But the 500 then restarts and I get a low DC voltage notification in Victron Connect. The DC voltage with engine running is 28.4v +.

I have watched the relay and the coil is holding the NC contacts open throughout, so the 500 should not be switching on.

There is no chance of both inverters trying to supply power as I’m using 2 pole interlocked contactors, so only 1 can feed the breakers.

The switch over between 500 and 3000 and back with no engine running works perfectly.

I’m not using any electronic control eg a bus/GX etc. The only thing is BT to Victron Direct.

[CRuMbS (Colin Stone)]

So, I’ve changed the relay and no change. When the engine is running the inverter is switching itself on even with the contacts of one remote switch open, the other remote switch is in series with contacts closed. I am pretty sure that with 2 remote switches in series, both have to be closed to switch on. If in parallel, then only 1 switch needs to be closed. This is only happening with the engine alternators producing electricity and the MP 3000 switched on. The other oddity is the low voltage alarm.
Might it be something to do with the charge detect voltage?? The unit and BT dongle don’t appear to record the alarm details, which isn’t very helpful.