alternator charging house battery

[gothicsurf]

I plan on a simple 12V auxiliary battery system charged by 200W solar array also connected to the alternator. Only issue I think would be to limit the charging current into the battery since it seems even a 100Ah SLA/AGM battery has a maximum charge current hovering around 20A, whereas the current from the alternator in my truck is rated for 60-70A. Is there a good way to limit the charge current, or maybe there is another approach?

Since the panels are likely only putting <5A into the batteries, I figure a current limiter from the alternator to <20A would be ideal. Then I could use 10/12 ga wire from there to the battery instead of 2/4 ga.

 

[highdesertranger]

alternators are self regulating you do not need another regulator in the system. just because it is rated for 60amps doesn't mean it will put that out if it did you would have fried your starter battery long ago. highdesertranger

 

[gothicsurf]

though I would like to be confident the gauge of wire chosen is sufficient for the current, even in the case that one of the two batteries is drained more than usual .. suppose I could use 10/12 ga wire between the two batteries with a smaller circuit breaker (maybe 50A) to protect the wire?

 

[highdesertranger]

also a lot of circuit breakers will only work in one direction. fuses work both ways. highdesertranger