Hi, we have multiple Victron chargers fitted aboard a pair of new vessels we have taken delivery of, however, the chargers have varying ratings of circuit breakers fitted in the 230V board. I’m struggling to find any information as to what size of breakers are required though, and hoped somebody here may be able to help?
The charger tyres are Skylla 24V 50amp and Phoenix smart 24V 25amp.
Thanks
Mark
Fuses and breakers exist to protect the circuit, not the device, so the correct breaker will be determined first by the ampacity of the wire used, and secondarily by the expected current multiplied by some factor (usually 1.25). Thus, the rating of required breakers will not typically be determined by the device manufacturer but instead by the experienced installer.
For instance, a DC circuit wired with 6AWG outside of an engine bay can carry 120A continuous, so should be fused or breakered no higher than that, while if it’s being used to carry 50A of current, obviously well below the maximum ampacity, one would reasonably fuse or breaker that circuit at 65A. Above the maximum expected current, below the maximum wire ampacity.
On the AC side, same concept. A 24/50 charger could not draw more than 7A from a 230vAC supply, so should realistically be breakered no lower than 9A, and no higher than the maximum ampacity of the wire being used to carry the AC current, which would hopefully be at least 14AWG; thus an AC breaker between 9A and 25A would be appropriate in that theoretical layout.
