I have a Multiplus 5000/48/70 and it's written on it 70A, so I thought that I was limited to 70A of current draw from the batteries.
I designed the system with a 100A DC breaker, but it was constantly tripping.
Then I was advised that this was not what I should have looked for. The current draw depends on the battery voltage, and the amount of power the Multi can take from the batteries (5000VA). So for 48V, I would get 5000/48 < 105A. So I put a 120A breaker.
Still, I'm getting the DC breaker tripped. 120A allows 500VA with a battery voltage as low as 41.677V (5000/120), this is pretty low. Still, I got the breaker tripping. I got to look at my BMV700 and the battery voltage was more around 44V at that time.
Is it possible the Multi is taking more than 5000VA, or is it possible that at the moment the breaker tripped, the Multi was taking so much power that the battery got below 41.67V?
I saw in VeConfigure that the minimum voltage at which the inverter disconnects is 37.20V, which is below what my breaker could accept, but the pre-alarm is above at 43.60V. Unfortunately I could not get my own settings.
Should I raise the minimum voltage to avoid tripping? Is that the correct value to look for or should I count a margin for the 5000VA?
Thank you.