Trying to switch on multiplus 2 straight out of the box to allow programming. With ONLY AC input connected, after switch on it trips the main breaker almost immediately. There are no batteries or AC loads connected
asked
Multiplus II, AC Input tripping
Do you have the case earthed as well as an earth on the ACIN side? House install? What is the amp rating of the circuit it is connected to? What else is connected to the circuit? You can try another socket by simply wiring a plug on the cable end and plugging it in as a test.
First, check for the obvious shorts or reverse polarity that sort of thing.
There is a good video walk-though on Victron professional on how to set up and configure the multiples 2.
I suggest you take the AC power off and turn the inverter on without any AC wiring attached and then ensure it is configured correctly for how you are going to wire it.
then install the input wiring and verify the polarity with a multi meter.
I hope that helps.
Sorry no answer but having same problem so wondering if this has been solved.
Decided to operate the unit again today in order to record the sequence of events befor failure. However it powered as would be expected NO tripping of the MCB Have now powered it on a number of times withou problem. Still concerned that it tripped a 32Amp MCB when first operated.
The initial start up of a unit has a huge current draw as it is charging up quite a bank of capacitors inside the unit.
If it is powered from a battery bank it can trip the bms (if it is lithium) and cause quite a spark if there is no DC disconnect and you are connecting directly to batteries, can cause burn marks. (Not best practice)
If from grid the same can happen to the AC breaker.
I have the same problem with my split phase setup.
Not sure if it's relevant but I had turned these off and on a few times with no issues after initially wiring them up. Once I updated to firmware version 475 they started tripping a 50 amp B curve breaker, I'm debating trying a C curve breaker. I was guessing it's inrush current tripping the breaker and if I reset the breaker 10-15 times they'll eventually turn on without it tripping.
This problem was with nothing connected to AC output. Also happens with or without batteries connected and with the multiplus switched to on or charger only.
I swapped the breaker to C curve over the weekend and it seems to be working well.
