I’m wondering if anyone has seen an issue like this before?
We have 2 x 100a batteries in a camper trailer.
We have been on the road today and we’re hoping to charge the batteries. However, instead we charged in this sawtooth pattern and barely put charge into the batteries at all.
We’re currently hooked up to power and the batteries are charging at a pretty constant 16amps.
Any idea as to what may have caused this?
Alternator not happy? Bad batteries?
We do suspect that the 200a of lithium are only holding 120-140amps (based on the smart shunt reading, however, not sure how to confirm that).
guystewart
(Guy Stewart (Victron Community Manager))
2
Hi,
It would help to also see the battery voltage reading as well.
Are you using a DC to DC charger, or just have the Alternator connected directly to the batteries?
If they are connected directly, I would expect it’s the alternator voltage isn’t getting high enough.
One typical cause of this is a loose cable connection or other cabling issue, frayed cable, poor breaker, isolator switch not making good contact etc. causing voltage drop on the cable which causes the charger to cycle. Sometimes the resistance is not too high and it just limits the current to a low stable value, sometimes it does the start stop if the resistance is higher.
