Specifically, I’m looking for the current spike that occurs on the DC input when the inverter is first connected to a DC source (e.g. a battery), under the following conditions:
Inverter is in the OFF state
No AC load connected
This is relevant for sizing pre-charge circuits and fusing. I’ve checked the 120V datasheet and the full product manual without success – the spec doesn’t appear to be published.
Has anyone measured this, or does Victron publish this information somewhere I may have missed?
The inrush current is more dependent on the source impedance of the connected supply than the device itself. As there will be quite a wide range of supply impedance, there is no single value for the inrush current that can be given.
In that case, can you tell us how large the capacitors are that need to be pre-charged? This will allow us to estimate inrush current based on input impedance, and total energy.
I’m trying to understand whether I need to build a pre-charged circuit.
for 12V, a precharge circuit is rarely needed. for some 24V systems it can help, and for 48V systems and above it should be considered essential.
Since I had a new one on the shelf, I tried to measure this with the capacitance meter, but that just gave out of range. These units are not intended for frequent connection and disconnection on the 12V side, so if there are frequent reconnections of power, then a precharge limiter would help. If more or less permanently connected (via a fuse) then precharge is not needed.