Probl

[Skooliemom]

I have

1-245w solar panel 8.15a 37.75v
1-Renogy Rover 30am charger controller
1-Renogy deep cycle AGM batter 12v 200AH
2-SPARKING 3FT Car Female Cigarette Lighter Plug Socket to Eyelet Terminals 12V Extension Cable with 10A Fuse (3FT) & (6FT)

I only use it for my 12v refrigerator and I have used it for a day and it drained my battery completely.?

Smad 12v/110v portable mini fridge 1.7 cu ft
I want to be able to charge my power banks.

I have ordered another battery same one
Do I need to add more Solar or what?

 

[Supervstech]

What kind of refrigerator? I mean, what type of cooling system is it?

 

[Skooliemom]

I hope this explains it.

 

[Supervstech]

An absorption type refrigerator is a one that can draw much higher watts, it can be more than 350 watts during running. Now that is crazy, your batteries will be loosing the power very quickly. Anything above 250 or 300 itself can be too much for batteries.

https://campergrid.com › rv-refriger...

 

[Supervstech]

That is a clip from a google search of power usage for absorption refrigerators...

second most power hungry cooling design... only peltier would be worse.

if you stick with that refrigerator, you do need to increase the bank, and the solar.

 

[Skooliemom]

I bought it because it was to be low draw guess I was wrong.

 

[MisterSandals]

I only use it for my 12v refrigerator and I have used it for a day and it drained my battery completely.

Something sounds off. "if" your battery was charged when you started and assuming no charging from solar, the use math looks like:

200ah of which 50% usable is 100ah
100ah x 12v = 1200wh
1200wh/24h = 50wh per hour

Your 2nd pic shows 65w. So on battery alone you will not make it 24 hours. In fact 1200/65 = 18.4 hours.

Was your solar doing ANY charging? Do you know how much?

In theory, your 245w panel charging for 5 hours would produce 1225wh. This is close to what your fridge uses but that's all under ideal conditions. Another battery will not make much difference unless you also have another panel.

 

[Fred S]

The answer in the pic you attached makes it seem like it is a "dual-powered" fridge, since 65w would be about right for this size fridge with a compressor. Assuming it does run at 65w, you can run it on that battery, but you'll have very little reserve for cloudy days.

At 65 watts, you need about 5.5 amps at 12v to run it. If it runs 50% of the 24-hr day, you'll need 12 hrs x 5.5 = 66 amp-hrs every day. If you get the equivalent of 5 hrs of sun, and average 10 amps from the controller, you're only getting 50 amp-hrs per best-case day. 2 panels might do it, but I doubt you could get by for even 1 cloudy day with only 2 panels, and your battery isn't large enough to carry over more than a day with a low charging rate.

3 panels may be enough. Note that they'd have to be in parallel, assuming your controller's input voltage limit is 100v. You should use 10 ga wire to the controller if you go to 3 panels. In good sunlight, 3 panels is more than your controller can make use of, but it will still be helpful in lower-light conditions. Same for 4 panels.

With 4 panels, the most efficient setup would be to wire two pairs in parallel, with each pair wired in series. This would provide maxes of 75v and 16a.

Also, as MisterS said, don't forget to try to avoid discharging the battery below 50% charge. Good luck!

 

[Skooliemom]

Ok so get new panels how many can I get and not have to change out my charge controller?

 

[Fred S]

There is no limit on the number of panels for your controller, you just have to make sure they are wired so that their total voltage is at least 15-20% lower than the controller's input voltage limit, which is probably 100v. For the panels you listed, you won't be able to put more than 2 in series, but you can put any number of 2-panel (series) pairs in parallel. Or any number of single panels in parallel. The cheapest route is to get 2 more panels and wire all 3 in parallel and see if that supplies enough for your needs. If not quite enough, get a 4th panel and wire them as 2 series pairs, then parallel the 2 pairs. This would be nearly 1000w in panels, and while your controller can only use 30a x 13.5v = 400w of that capacity in full sun, the extra panels will help with charging in cloudy conditions.

 

[MisterSandals]

There is no limit on the number of panels for your controller,

Categorically wrong!

you can put any number of 2-panel (series) pairs in parallel.

Categorically wrong!

There is DEFINITELY an amp limit for the input from solar.
These are the limits I found in a quick search:

Wanderer Li 30A PWM Charge Controller

The Renogy Wanderer-Li is a 30A PWM solar charge controller that incorporates efficient PWM crediting boost battery life and improving system performance.

www.renogy.com

Max. PV Input Power: 400W
Max. PV Input Voltage: 25 VDC

I would suspect the max pv input current to be in the 400/25 = 16 amp range. (? up to 25?)

 

[Fred S]

For PWM, true, I should have clarified. I can't edit the post any longer or I'd add that note. Thanks for the catch.

The OP's controller is MPPT. For MPPT, I don't think "amps" really matters, only the voltage. The controller is limiting amps. I will double-check, thanks.

 

[MisterSandals]

A 30a controller will max out at 30a delivered to the battery, but the array may be capable of providing way more amps. E.g. this is why "overpaneling" doesn't harm anything.

It does not matter if its MPPT or PWM. If you exceed the max input volts or amps, you will fry the SCC. You cannot exceed input volt or amp limits.

 

[Supervstech]

It does not matter if its MPPT or PWM. If you exceed the max input volts or amps, you will fry the SCC. You cannot exceed input volt or amp limits.

Not really.
Exceeding the max amps on most mppt controllers simply wastes solar production. Since the max amps is set by the controller, it will operate up to the maximum and then lock it in there. Sure, operating at 100% for extended time can burn out the controller... it shouldn’t.

 

[Skooliemom]

So this is my understanding.
I need more solar and I could get 3 more panels of the same kind tie them in parallel then series and I should be fine. I am going to keep the other battery because I have already paid for it.

 

[MisterSandals]

Not really.

Do you think that one can put any number in parallel? This was my original objection.
>>
but you can put any number of 2-panel (series) pairs in parallel. Or any number of single panels in parallel.
>>

 

[Fred S]

I should be in bed, ha. Yes I had 2000w of panels on a 30a mppt for a year. I don't know why an Isc is sometimes listed as a limit for input to an MPPT controller. Especially the Isc for a given panel, since any combination of panels and series/parallel could be in use.

 

[Fred S]

Yes, the voltage is the "pressure" that could cause the electronics harm, but having amps "available" is ok - because the controller chooses whether to use them, so to speak. Again, for MPPT types.

 

[Fred S]

Skooliemom, in my opinion, the 4 panels and the 2 batteries you described will do it for the small fridge and charging phones, with ample sunlight. I don't know what the "power banks" are that you described.
For longevity, you should not run the batteries down any more than 50%. You will have to ask the battery manufacturer how they recommend you measure that.

 

[Skooliemom]

Power banks that you can charge your phone with if your out around town.

 

[Supervstech]

Do you think that one can put any number in parallel? This was my original objection.
>>
but you can put any number of 2-panel (series) pairs in parallel. Or any number of single panels in parallel.
>>

Yes.
The controller may not have the ability to flow continuously at max rated watts, but having infinite watts available should do no harm unless VOLTS are exceeded.

 

[MisterSandals]

Yes.
The controller may not have the ability to flow continuously at max rated watts,

I will take your word on this as i snack on my plate of crow.
But i am really wondering about the amps. Putting a lot of amps into a SCC rated at 400w (there is a reason for this limit!) cannot be safe. Recommending exceeding this by 150% to a newbie, in her schoolie dwelling is not something i will do.

 

[Supervstech]

I will take your word on this as i snack on my plate of crow.
But i am really wondering about the amps. Putting a lot of amps into a SCC rated at 400w (there is a reason for this limit!) cannot be safe. Recommending exceeding this by 150% to a newbie, in her schoolie dwelling is not something i will do.

Remember... amps are watts IN USE.
If the controller only processes 800W, it doesnt matter if you hook up 2000W... it will only take 800.
The only issue is if the controller is not rated to process full wattage constantly.

 

[MisterSandals]

If the controller only processes 800W, it doesnt matter if you hook up 2000W

Thanks. I will have to be ignorantly content for now, not understanding how an infinite amount of energy can be controlled and to process only what is wanted, so easily, inside an MPPT controller.

 

[Supervstech]

Well...
A car battery has over 800A available in it.
But the starter only pulls out what it needs to turn over the engine...
Utility poles have 10,000A potential... only takes out around 90A or less if the lights are off...