Solar and Battery Upgrade Plan Questions and Suggestions

[Rhumblefish]

Originally Posted by xLOGREx

I'm guessing that if I plug my 100w suitcase panel into the port on the side of my trailer that it will also drag down my roof panels output?

Nope. Completely separate systems, each with their own charge controllers - only place those panels will see each other is as they are connected at the batter(ies).

[jlankford]

FYI, a Renogy 200W rigid solar panel has exactly the same dimensions and specs as the factory GP panel, at less than half the price. I added two 200W Renogy panels to my existing 200W GP panel, and they work fine together. A 30A GP SCC can handle 600W - the 30A refers to the input current spec, not the output current.

[Aussieguy]

PWM controller you could put 600w on it
BUT the output to the battery at max will be 400 or a bit more..

controller will only input/output 30amps (maximum specified for the controller)
battery charging voltage = 14.4v
Max can be sent to battery 14.4 x 30 =432w

600w of panels if you are in a BAD solar production area ..... may/would be of some benefit as long as you don't exceed the amps of the controller

if you in a good solar area ..... it is a waste of a panel
better off increasing the controller's amperage

good reading here from Renogy
https://www.renogy.com/learn-system-sizing/

[jlankford]

Originally Posted by Aussieguy

controller will only input/output 30amps (maximum specified for the controller)

This is not correct. We've had this discussion on the forum before. The GoPower SCC specs seem to be different than other brands. The 30A spec is referring to the input current limitation, not the output. Please note on the attached spec sheet - the input current limited to 30A, while the output current spec is stated to be 37.5A.
I have seen output as high as about 33 amp from my GP 30A PWM SCC. That's 475 watts at the 14.4VDC charging voltage. Assuming the 79% efficiency estimate on your Renogy link for a PWM controller, that would mean I was getting an input wattage of 601 watts from the PV at the time. Granted, that high current is very rare for my roof mounted panels - I must have seen that 33A output at high noon.

[Aussieguy]

is Gopower playing with numbers?
30 amp input
37amp out ?

PWM 's usually don't have ability to change amperage
Go power's own install manual states the controller will just pass through what the panel's can produce... you have to limit the amps with the panel setup


if they can output 37 amps GOOD
no-one else I know can increase 30 amps to 37..... with a PWM
they should be selling them like hotcakes ... or are people just ignore their ??claims??

[tomkatb]

Lived in Belville several years on the lake.

Tons of fun.

I remember one Fourth of July. Drank a case of wine! It was cloudy and Rainey for four days. No lake activities.

Tons of trees.

My observation of Michigan was it is not a good place for solar. Also too far north.

Still visit Wyandotte frequently.

SOK batteries have a built in battery monitor that is more than adequate.

I would get two 280 ah SOK batteries. That alone would likely get you 4-5 days or more. A back up 2000 watt generator. $1100 for the Honda. Would power the ac if necessary. Or more solar. A flat 100 watt panel could produce 25 ah. But, not so much up there.

There are DOE documents that address sunshine. Michigan is sort of dreary.

[jlankford]

Originally Posted by Aussieguy

is Gopower playing with numbers?
30 amp input
37amp out ?

PWM 's usually don't have ability to change amperage
Go power's own install manual states the controller will just pass through what the panel's can produce... you have to limit the amps with the panel setup


if they can output 37 amps GOOD
no-one else I know can increase 30 amps to 37..... with a PWM
they should be selling them like hotcakes ... or are people just ignore their ??claims??

If the design of the SCC includes a buck converter, then the output current can certainly be higher than the input current. Having said that, I know nothing about the design details of any brands' PWM controllers.