I have a diesel, so two batteries for truck, there are two 6-volt for the Truck Camper, and I want to put a deep cycle battery in the cargo trailer.The Camper does have 200 watt solar to charge its batteries, but is hooked to alternator via switch. The cargo trailer would be on a switch also, and maybe one day have its own solar 100 w panel.How many batteries can the alternator take?I don't want to over-work it and burn it out.I think it is just a stock alternator, but not sure what, could be 130amp, or as low as 95 (doubt it for a diesel) or hopefully more, but I do not know. Let's assume about 136 amp as is what I see sold for this truck.Heavy gauge cables to other batteries.

You don't state what type of truck or the system voltage. In theory, you could use up to 100% of your alternators capacity to charge your batteries but IMO, that would not be a good idea because your truck needs some of the alternators capacity for "other" electrical consumers too. Chances are that your electrical system is under sized to run more that about 30/40 amps to your batteries on a continuous basis without locating its weak link for you. IMO when OEM's call out an alternators specifications, they mean MAX, not continuous.Chum lee

Chumlee, lol. Is that a character from the TV show? He would ask that. It is like 99% of vehicles at 14 volts. Truck is blue if that helps visualize it. It has a camper sitting in the bed too, lets say it is a regular pickup truck with typical charging system. I do not know the math otherwise, nor calculated amperage uses. Typical will suffice for now.136 amp alt, 14 volt system as stated before. Typical otherwise.

The real question is how long will it take to re-charge X number of batteries. Assuming the non-starting batteries are 6V deep cycle golf cart batteries and they are at 50% SOC and you have no DC-DC charge controller, the answer is several days !

theoldwizard1 wrote:Assuming the non-starting batteries are 6V deep cycle golf cart batteries and they are at 50% SOC and you have no DC-DC charge controller, the answer is several days !This. If you're not going to also invest in a DC > DC charger such as a CTEK 250SA then you're wasting your time & effort trying to use your truck's alternator as a source for recharging depleted deep cycle batteries.

The following problems were encountered while processing your request: > Your message contains invalid formatting. Please use the toolbar provided to ensure proper formatting.Well glad i typeda long response, just to be denied when there is Nothing different I've done with thousands of other responses.Getting contemptuous of this forum's issues and the captcha BS

Alternator: How many batteries can it take? | Good Sam Community

twodownzero
Explorer
Feb 22, 2019
The batteries will only take whatever current they are capable of taking. 136 amps would charge 2 golf car batteries in less than two hours from 0% SOC, but no battery will sustain that kind of charge rate. If I were you, I'd make sure your charge circuit is capable of 40 amps continuous (at least 8 gauge wire, bigger if the length is long) and call it a day.

The real question is, how much power do you need? If you're depleting your battery bank, you probably need more battery capacity before even thinking about how to charge them, especially if you already have 300 watts of solar.
landyacht318
Explorer
Feb 22, 2019
The following problems were encountered while processing your request:

> Your message contains invalid formatting. Please use the toolbar provided to ensure proper formatting.

Well glad i typeda long response, just to be denied when there is Nothing different I've done with thousands of other responses.

Getting contemptuous of this forum's issues and the captcha BS
SoundGuy
Explorer
Feb 21, 2019
theoldwizard1 wrote:
Assuming the non-starting batteries are 6V deep cycle golf cart batteries and they are at 50% SOC and you have no DC-DC charge controller, the answer is several days !

This. If you're not going to also invest in a DC > DC charger such as a CTEK 250SA then you're wasting your time & effort trying to use your truck's alternator as a source for recharging depleted deep cycle batteries.
theoldwizard1
Explorer II
Feb 21, 2019
The real question is how long will it take to re-charge X number of batteries. Assuming the non-starting batteries are 6V deep cycle golf cart batteries and they are at 50% SOC and you have no DC-DC charge controller, the answer is several days !
ajriding
Explorer II
Feb 21, 2019
Chumlee, lol. Is that a character from the TV show? He would ask that. It is like 99% of vehicles at 14 volts. Truck is blue if that helps visualize it. It has a camper sitting in the bed too, lets say it is a regular pickup truck with typical charging system. I do not know the math otherwise, nor calculated amperage uses. Typical will suffice for now.
136 amp alt, 14 volt system as stated before. Typical otherwise.
Chum_lee
Explorer
Feb 21, 2019
You don't state what type of truck or the system voltage. In theory, you could use up to 100% of your alternators capacity to charge your batteries but IMO, that would not be a good idea because your truck needs some of the alternators capacity for "other" electrical consumers too. Chances are that your electrical system is under sized to run more that about 30/40 amps to your batteries on a continuous basis without locating its weak link for you. IMO when OEM's call out an alternators specifications, they mean MAX, not continuous.

Chum lee

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