Solar Panel Controller Advise

This little 20A guy may burn out with 280W panel if you use it where Jim in Denver uses his. Yes, your amps may never reach 20, but if they will, it's your money against Chinese quality (and you can't demand 20A controller to withstand 21A for too long anyway).

In light of this, I would treat this combo like BFL13 treats his $20 PWM controllers - as a toy. Which in turn means that you shouldn't pay $100 or so. It also means that you shouldn't rely on it as your main source of energy - but it sounds like this is fine with you.

The panel is a little overpriced, by today's markets.

1L243 wrote:

What do you guys think would be a good offer to make for this system?

280W*$0.75=$210, plus 30-40 bucks for a toy with blinking lights. $240-250 total. And I would only buy it if your batteries are somewhere inside, and the controller can be mounted in the same space. Because without remote temp sensor and with batts outside your voltages will be always off.

JiminDenver wrote:

1L243 wrote:
Question.. How do I know what panels will work with my 12 volt system?

Jim can you link me that panel for $202. I was on that site and cant seem to find it.

Here is the link for the 270w at $202

click

Damn it Jim! Your gonna cost me money.

-Jeff

1L243 wrote:
Question.. How do I know what panels will work with my 12 volt system?

Jim can you link me that panel for $202. I was on that site and cant seem to find it.

Here is the link for the 270w at $202

click

Hi

What makes panels work with your 12 volt system is the controller. High voltage panels require an MPPT controller and they are a premium price (for 8% more solar harvest).

Here is a 140 watt panel for $154. http://www.solarblvd.com/p2582/Solar-Cynergy-140-Watt-12-Volt-Solar-Panel/product_info.html?osCsid=0765826af670ba33d03682b08b25d3a7

Get two of those with a decent PWM controller.

Here is a link to a panel @ $174: 235 watt 24 volt 0.74 cents per watt

This option requires an MPPT controller.

1L243 wrote:
Question.. How do I know what panels will work with my 12 volt system?

Jim can you link me that panel for $202. I was on that site and cant seem to find it.

About what he paid then, so no special deal for you. If you are where you can pick up panels yourself from one of the low-priced places or if they have no shipping charge to you, then you are wide open to other options.

If you would have to pay shipping for another option, then the OP deal could work since there is no shipping, but IMO only if he would take $400. That would be like 300 for the 280 and 100 for the $125 controller. (Despite what the others say, I think that would be a decent controller, especially since you intend to mount the panel flat)

--The panels work with 12v systems even if they are 37volt panels because they work through the MPPT controller which is what works with the 12v batteries.

Question.. How do I know what panels will work with my 12 volt system?

Jim can you link me that panel for $202. I was on that site and cant seem to find it.

He was wanting $450 for the 280 watt panel, the controller and connecting cables and connectors...

Unyalli wrote:
This is one nice little solar controller. Morningstar Sunsaver MPPT




-Jeff

Those are nice and recommended for what they can handle but the most I'd hook up to it is 230w and that's at lower altitudes. Where I camp it would be clipping power a good portion of the day.

Hi KJ,

2oldman has a 24 volt battery bank.

800 w / 24 v ~= 33 amps.

KJINTF wrote:
2oldman

With your system at over 100Vdc of array voltage, the efficiency of the buck conversion within the MPPT controller is limited. I would guess if you did a series parallel array configuration with a Voc of say 50Vdc you could gain another 5 to 7% increase. However this is just a guess without ever actually seeing your system.

This is one nice little solar controller. Morningstar Sunsaver MPPT




-Jeff