(2) 12V Solar Panels....Series or Parallel?

The bogart controller is good for op to 36A and will then taper of. I have 4/150V panels= 600V feeding 2 260A flooded batteries with temp sensor and no issues haven't had to ad water in 4 months.
Frank

Most people either do a search here, or do their research/homework first, before they buy their charge controllers,and solar panels.

I am going to "Do" the toad before I depart to the south. Now that I have found "Locomotive Grade" cable the battery is going to be relocated to the trunk and it looks like a Sam's Club AGM might be in the offing. A hundred forty dollar 68 amp hour group 34 flooded or a 179 dollar group 31 AGM? Duh!

http://www.dekabatteries.com/assets/base/0139.pdf

find the agm charge & float at various temps, bottom page 11

If ya buy into IUI use concord AGM otherwise use generic AGM no finish!

specs

http://www.eastpennmanufacturing.com/wp-content/uploads/Intimidator-Marine-Flyer-1741.pdf

I just picked up the last two AGM batteries at Sam's Club within a 150 mile radius of my house! Quite a challenge finding them. But for $179 each...it's a SMOK'N Deal!

I need to look through the install literature that came with the Bogart and call Duracell to get the specs on the batteries.

Duracell 31DT

Rbertalotto wrote:

As I read and learn more, it appears the input AND output need to be either 12V or 24V........

That's the benefit of PWM, no transformer to waist energy on small systems.

I'm interested in what battery profile you will pick with your G31 AGM?

Forget it even says 24 volts

Not so fast! :) I posted my good results with 24v panel and 24v batts using both MPPT and PWM. 24-24 was the same amps for both and that beat the amps using 24-12 MPPT (controller efficiency suffers with the buck conversion)

Two 12s in series at 36 cells each would also solve the limitation with 24v and a single 60 cell panel that can arise in some scenarios.

However, getting 12v to the rig from the 24v batts is an "issue". There are several ways to get by that too, but you need to start out with the 24v planned so you buy a 24v inverter, a 24v charger for when solar is no good, and some kind of 24-12 converter. (Although you can run your existing 12v converter from the 120v inverter on the 24v bank, if the solar supply is plentiful in daytime to keep up with nighttime 12v use as well)

I liked being able to run the lower cost 24v panel with the lower cost PWM vs expensive MPPT or expensive 12v panels with the low cost PWM. You can't find low cost 12v panels and low cost PWM anymore sadly.

keep them parallel , its the only way that is sensible with PWM controller
if you go series the amps will be cut in half, voltage to the controller will double, and the controller will knock it down to 14 for charging
you will loose power IF you go series

Rbertalotto wrote:

As I read and learn more, it appears the input AND output need to be either 12V or 24V........

So, if 24V, how do you utilize this in our 12V systems?

1) Yes. That's the problem with any PWM - voltage in and voltage out is the same, minus tapering.

2) You can't. This can be done with MPPT controller. Forget about series with PWM.