Charge controller question

[mrm11759]

Hi Vanners:  I am building out a 1998 E 250 van and have a question about the electrical system.  I will have two 125 Ah AGM batteries in the van that will be supplied by the engine alternator via a smart battery isolator and shore power.  My question is do I need a charge controller to regulate the voltage when charging the batteries?  I will also have a 1500 W inverter/Charger [Samlex Solar PST-1500-12 PST Series Pure Sine Wave Inverter] connected to the batteries.  Just not sure if the inverter/charger and the battery isolator will overcharge the batteries.  Any assistance is appreciated!

 

[Boondock Saint]

Not according to the conversation I had with the Exide engineers about this very thing. I charged 2 deep cylces from the alternator voltage of my Wrangler, worked like a charm.

 

[mrm11759]

Not according to the conversation I had with the Exide engineers about this very thing. I charged 2 deep cylces from the alternator voltage of my Wrangler, worked like a charm.

Thanks!

 

[highdesertranger]

ok a couple of points,

relying on the alternator as the sole charge source is a poor choice.
you mentioned shore power, how often?
it's takes many, many hours of driving at highway speeds(5-8) to recharge a depleted battery.
sitting and idling won't cut it.

don't get me wrong the alternator SHOULD be used as a SECONDARY charge source.
an alternator is self regulating.
what is this "Smart Battery Isolator" that you are talking about?
lots of details missing, please fill us in a little better and we can give better advice.

highdesertranger

 

[jonyjoe303]

its next to impossible to overcharge your agms even with the alternator, if anything you might undercharge them. Check to see what the max charge voltage is, i got 2 agm's that require 14.7 volts to reach a full charge, most alternators max out at 14.4 volts. i have a special dc to dc charger to top them off at 14.7 volts.

Also if you got any voltage drop from alternator/isolator to the batteries, they might not even reach 14.4 volts. It would be a good idea to check the voltage at the battery terminals to make sure they are reaching at least 14.4 volts.