Charging 6 volt batteries in series

[Sunking]

If you have high voltage and low amperage coming from your PV array, won't a charge controller regulate it so that the battery is charged correctly?

Yes to an extent with respect to voltage will be regulated, but not current. What you are talking about is a MPPT Charge Controller where Output Current = Panel Wattage / Battery voltage. So armed with that info you automatically know that Battery Voltage x Current = Wattage. So armed with that info how much panel wattage does it take to generate a C/10 charge current on a 12 volt 225 AH battery? 12 volts x 22.5 amps = 270 watts.

FWIW none of that applies to a PWM Controller because with any PWM controller Input Current = Output Current. So to generate 22.5 amps with a PWM controller we have to use standard Battery Panels which have a Vmp of 18 volts. So 18 volts x 22.5 amps = 405 watts to do what a 270 watt panel using MPPT.

In either case the charge current is determined by panel wattage.

[Beanyboy57]

Certainly assuming you are wiring them in series to make 12 volts.

Between C/12 (18.75 amps) and C/8 (28.125 amps)

If you have high voltage and low amperage coming from your PV array, won't a charge controller regulate it so that the battery is charged correctly? Assuming that the charge controller is programmed to the correct type of battery.

[Sunking]

Can I use a 12 volt charger for this application? I will be running 2 Trojan T105 225AH batteries.

Certainly assuming you are wiring them in series to make 12 volts.

At what amperage should I charge them at? Thanks!

Between C/12 (18.75 amps) and C/8 (28.125 amps)

[Naptown]

Yes you can and you should be charging at about 20-23A

[FarBeyondDriven]

Can I use a 12 volt charger for this application? I will be running 2 Trojan T105 225AH batteries. At what amperage should I charge them at? Thanks!