Solar panel advise

[Nan_wpg]

Watts are watts. Volts times amps. I get that.

pwm= panel must match battery.

mppt= it doesn’t matter? Hook up whatever panel and mppt will charge at whatever is needed?

 

[Rednecktek]

Watts are watts. Volts times amps. I get that.

Yup

pwm= panel must match battery.

Panel Vmp must be 3-5v over battery charging, I.E. ya need to have at least 17v to charge a 12v, and 31v to charge a 24v, but anything above that is wasted.

mppt= it doesn’t matter? Hook up whatever panel and mppt will charge at whatever is needed?

You still need the minimum. A 40v panel will charge a 24v battery because the MPPT can take the higher voltage and kick it down to lower voltage. A 17v panel (your bog standard "100w panel") doesn't get kicked up to feed a 24v. It goes down, not up.

MPPT gives you Voltage Down -> Amps Up
PWM gives you Voltage Down -> Panel Amps max
Neither will give you Voltage Up

 

[Browneye]

Right. Generally you'll see a configuration table for various system voltages like this:

Your SCC spec will have a max voltage rating, so you wire your PV to suit.

And no, you can't charge a 48V battery with 12 volts of solar power.