48 volt battery charging

[Nazproperties]

FWIW you can get 2 golf cart batteries which are 6 volt 225 AH for $300. That is more than twice the capacity of 100 AH

Sounds like I need to change my thinking to 6 volt golf cart batteries X 2. Thank you everybody for all your input, this forum has really helped.

[ButchDeal]

Sounds like I need to change my thinking to 6 volt golf cart batteries X 2. Thank you everybody for all your input, this forum has really helped.

or you could just get one 8A4D 200Ah 12V AGM which can handle higher rates of discharge and charging for $380 instead of two 6V batteries.

or an 8A8D 245Ah 12V for $460 :
http://www.batterymart.com/p-12v-245...d-battery.html

[SunEagle]

or you could just get one 8A4D 200Ah 12V AGM which can handle higher rates of discharge and charging for $380 instead of two 6V batteries.

or an 8A8D 245Ah 12V for $460 :
http://www.batterymart.com/p-12v-245...d-battery.html

And those batteries weight over 150 lbs where a 6v 232 Ah battery weighs about 60 lb max. Better get a small fork lift to move those 12volt ones around.

[Nazproperties]

solar panel connections

And those batteries weight over 150 lbs where a 6v 232 Ah battery weighs about 60 lb max. Better get a small fork lift to move those 12volt ones around.

With my CC set at 12 volt and the 2 6 volt batteries wire in series for 12 volts would the connections be + on one battery and - on the 2 battery?

[SunEagle]

With my CC set at 12 volt and the 2 6 volt batteries wire in series for 12 volts would the connections be + on one battery and - on the 2 battery?

Yes. You would first connect the - of battery 1 to the + of battery 2. That gets you 12volts between the + of battery 1 and the - of battery 2.

Then connect your charge controller to the + of 1 and - of 2. You would connect your inverter to the same terminals.

[Nazproperties]

panel voltage output

With my 4 panel system, wired in parallel and each panel rated to produces 100 watts and Voc 21.6v and Vop 18v, is the output still going to be Voc 21.6v and Vop 18v and only increasing the watts to 400?

[Sunking]

Power and current add in parallel. Parallel is less efficiency and cost more

Power and voltage add in series. Series is more efficient and cost less.

[Mike90250]

Power and current add in parallel. Parallel is less efficiency and cost more
Power and voltage add in series. Series is more efficient and cost less.

The other half, is the charge controller. under 400w, it's cheaper to use the PWM style (70% efficient). Over 400W, MPPT is the suggested (95%) And if you go series, you will need MPPT to downconvert the 60V from the 4 PV's to 15v for battery charging.

[Sunking]

The other half, is the charge controller. under 400w, it's cheaper to use the PWM style (70% efficient). Over 400W, MPPT is the suggested (95%) And if you go series, you will need MPPT to downconvert the 60V from the 4 PV's to 15v for battery charging.

I think you meant 200 watts right? I can build a 200 watt MPPT system for less than an equivalent 300 watt PWM system.

[Nazproperties]

watts

I think you meant 200 watts right? I can build a 200 watt MPPT system for less than an equivalent 300 watt PWM system.

Wouldn't 4 x 100 watt panels wired parellel not yield 400 watts? And increase to Amps?

[Sunking]

Wouldn't 4 x 100 watt panels wired parellel not yield 400 watts? And increase to Amps?

Yes but PWM is only 67%. Your 4 battery panels in parallel at best will generate 22 amps. With MPPT I can generate the same current with 280 to 290 watts. Not only that I could use a single much less expensive grid tied panel.
.