Need help wiring up a small solar set-up.

[marco]

I need some help folks. Here's what I got and what I want.

Two 150 watt solar panels rated at ~20v
Two 75 watt panels rated at ~20v
not sure about the listed amps but will post asap (if needed)

Four 12 volt deep cycle batteries and two 6 volt Trojan T-105's ( I am unsure of the amperage but I'll look and re-post asap)

Outback flexmax 80 MPPT

Xantrax 1800 powerhub inverter (I am thinking of replacing this juice sucking POS)

I want to be able to run a small laptop computer, one or two LED lights, but my biggest hurdle is to be able to run my Enviro III pellet stove which lists the amp draw at 3 amps ( 120v x 3 = 360 watts) I disconnected the ignitor and will light it manually as the surge and current draw would be too much IMO.

So ! What is the best way to hook up my solar array to hit the sweet spot? I know I can hook them in series to run higher voltages safely into my flexmax ( no higher than 144 is listed in my manual )

I have tons of available sun here in Colorado. Will 450 watts of solar panels be enough to fully charge my batteries and most importantly will there be enough storage to run my pellet stove at night?

I would think running my batteries for 24v's would be best? And if so could a simple schematic be laid out for me..same goes for my panels.

Any help would be appreciated..also love the website and forum !

[marco]

As I stated above if anyone needs more info to help dial this in just let me know. Thank you !

[rreidnauer]

The MPPT will handle mixed panels well. I'd hook the 150w ones in series, the 75w ones in series, then parallel the two. Will give you approx 12.8 amps @ 35 volts peak performance. (Ideally, all in series would be best, but on mixed wattages, not a good idea)

Batteries are a little trickier. A 24v system would be best utilizing what you got. I'd probably try paralleling all the 12v, and series the the 6v to the 12v to get 24v. Trying to series the two 6v together then paralleling to the 12v will lead to incomplete charging of either the 12v or 6v depending on capacities.

Really tough getting an efficient system with a mixed bag of components. I'm still looking for more of the panel's I have (long since discontinued) to add to my array, as I don't want mixed components.

[rreidnauer]

Test the pellet stoves actual power usage. Good chance it's lower than rated. Then, I need to know the amp-hr of the deep cycles (at 20hr discharge rate) to calculate how long the pellet stove can run. But it does sound like you might have enough battery to get you through the night.

[marco]

I didnlt read your posts yet Rod..just wanted to lay this on...here's some more info:

my 4 large 12v batteries are NAPA part # 7271 1400 CCA 1750 CCC@ 32 F ( I am going to google that part number...maybe they are not deep cycle..hmm)

two panels are 150 w with 8.7 amps and the other two panels are 75 w pushing 4.3 amps.

i am going to buy one of those watt reader plug in testers..they look slick. I'll be back in two shakes of a rattlers ass-end.

[marco]

googled the batteries...hmmm...dont think they are deep cycle. grrr.
https://www.napaonline.com/napa/en/p/NBR7271_0508118836

[marco]

Thanks Rod, any possibility you could draw me a pic of the connections for the batts and panels. i know parallel is + to + and series - to + but I get lost when stringing them all together.

[marco]

no edit feature? bummer

heres the skinny on the trojans (not the condom variety btw)

Trojan T 105 : 185 (5 Hr Rate AH), 225 (20 Hr Rate AH)
Capacity Minutes: 447 min @25 Amps, 115 min @75Amps

Maybe scrap those NAPA batts and go with 2 more trojan 105's ?

[rreidnauer]

You could use the other batts, they just won't hold up as long as deep cycles in the long run, mainly due to thinner plates.

All the same batteries makes life much easier.

Working up a basic drawing now.

[rreidnauer]

Done!

wiring.png