Series or parallel for cold set up

[Cubsfan143]

Hello. Great forum. Learned a lot. But always need more data! Ha. Here is my situation, It’s an off grid setting. High mountain cabin. I was gifted most of this set up so while I’m sure you have good intentions, I’m not asking what I “should” have bought or etc…. Just trying to decide the best way to set up what I have to work the best. Thanks.
I have 100amh renogy smart lithium with internal heater. 2- 330w Trina panels. Vmp 33.6 v, voc 40.4v, imp 9.67amps, isc 10.30amps. So my question is based on the need for that internal heater to kick on it takes 4amps of incoming power. So I have long winter there. 2 or 3 months of temps from 0-32 degrees F. And it’s in a valley so the low winter sun only will hit the panels about 3hrs a day in the winter. and thAts the best spot I can find with trees and etc…I am only out there about 3days every 2 weeks. And currently running all my crap I only use about 2.5 amps/hr. So while having the battery be able to re charge daily would be optimal, I can be there 3 days with no charging of battery at all. But if the temp never goes above 32 the battery won’t ever re charge while I am gone. So back to my question, with only 3hrs of sun am I better off putting my panels in series and parallel? I’m thinking parallel to get more amps coming in to make sure that internal heater gets turned on and can warm up battery to take a charge? The panels will be mounted attached so no way to have at different angles for shade or what not. I don’t have a controller yet until I know how I will connect panels.
I am open to the heat pad idea. Just not sure if I will use more power doing that than I can re charge?

Thanks for any and all help and suggestions

 

[yodamota]

whether the panels are in parallel or in series will have no effect on the battery side of the charge controller.

example
my charge controller is receiving 124VDC at 9 amps from the solar panels. It comes out as roughly 37.2 amps at 30VDC to the batteries

 

[Cubsfan143]

Thanks for the response and info. That’s what I’m looking to learn and why I’m asking this stuff. But I honestly don’t know exactly what your telling me? So are you saying even if I had 5 10amp producing panels in parallel the power going into my batteries will still be throttled by charge controller? Or what and I not understanding. Sorry for sounding dumb. I’m just trying to understand. Your point is parallel or series my battery will get the same amount of amps for charging?

Thank you

 

[yodamota]

Thanks for the response and info. That’s what I’m looking to learn and why I’m asking this stuff. But I honestly don’t know exactly what your telling me? So are you saying even if I had 5 10amp producing panels in parallel the power going into my batteries will still be throttled by charge controller? Or what and I not understanding. Sorry for sounding dumb. I’m just trying to understand. Your point is parallel or series my battery will get the same amount of amps for charging?

Thank you

yes the solar panel circuit is separate from the battery circuit.

your current panels
2- 330w Trina panels. Vmp 33.6 v, voc 40.4v, imp 9.67amps, isc 10.30amps.

hooked up in parallel will spit out roughly 19.2 amps at roughly 33.6v

in series the will spit out roughly 67.2v at 9.67amps

Your charge controller will take either one of those voltages whether its 67.2VDC or 33.6VDC
change it to 14.4VDC at whatever amps the batteries are requiring.

67.2vdc x 9.67amps = 650 watts.

650watts / 14.4 = 45.1 amps potential to go into your batteries

 

[yodamota]

What charge controller are you thinking of getting?

 

[Cubsfan143]

Ok, thanks for explaining that. I do understand the difference. I guess what I still am trying to decide or get more clarity on is then does it make more sense to go parallel or series for my application. Which is trying to make sure
With the weak short days winter sun, would going parallel give me a better chance to make sure my battery was getting the minimum of 4amps needed to turn on the internal heater so the battery can accept a charge?
Once I know which way to wire the panels, then I’ll know what size charge controller I need. I am looking to get a victron so I can feel good I have some quality in that spot.
Thanks

 

[yodamota]

How far will your panels be from your charge controller?
Hooking them up in series allows for the least amount of voltage drop due to distance. Hooking them up in series allows the charge controller to take advantage of the MPPT. Allowing the charge controller to find the best voltage to get the most power from any given day weather its cloudy/sunny.


I would personally hook those two panels up in series along with using a 100/50amp victron charge controller.

There are plenty of threads on here about parallel vs series connections. Maybe find some of those threads to read thru. I believe parallel connections handle shade better than series. Meaning one panel can have shade on it at a reduce amount of power output, while the other panel will perform at full capacity. Both panels would be effected if one panel was shaded in a series connection.