starting off small but turning into more

[redbank]

Those cables will create 4 panels wired in parallel but you will now need to include individual fusing for each panel. Just using that cable is not safe.

I do have an inline fuse.

I want to thank everyone for their help and time. much appreciated.

[Mike90250]

........

Second question, if I find myself running my single 105ah 12v battery low during a weekend with bad weather do I wire it up in series or parallel?

Wire the panels in parallel. you can use the branch connector.
Wiring panels in series does nothing for you but waste a panel.

[SunEagle]

maybe you are not understanding my question or the connector I want to use.

https://www.renogy.com/4-to-1-solar-...mf-ffffm-pair/

This should put them all 4 in parallel, series if I understand would be to attach one panel to the next panel and so on.

Those cables will create 4 panels wired in parallel but you will now need to include individual fusing for each panel. Just using that cable is not safe.

[redbank]

With the specs you mentioned earlier, you can only run all 4 panels in parallel. 2 in series would overvoltage the controller

maybe you are not understanding my question or the connector I want to use.

https://www.renogy.com/4-to-1-solar-...mf-ffffm-pair/

This should put them all 4 in parallel, series if I understand would be to attach one panel to the next panel and so on.

[Mike90250]

With the specs you mentioned earlier, you can only run all 4 panels in parallel. 2 in series would overvoltage the controller

[redbank]

So if I used a branch connector and positioned two 100w panels SE and two 100w panels SW and used my better CC (rated at 400w maxium input power and 42v maxium solar input voltage) I should be okay? The CC notes there is an overload protection if it matters.

Second question, if I find myself running my single 105ah 12v battery low during a weekend with bad weather do I wire it up in series or parallel?

[Ho jo]

With 400 watts all aimed in the same direction my amps peaked at 26.
In a SE SW orientation peak amps would be
less.
A 100 volt 30 amp controller would be well matched.

[ewarnerusa]

...If I took your advice and wired two panels in series and face them SE and the other two SW what would be the best way to switch between the two panels? I am assuming I need to create some sort of switch before it reaches the controller so I can limit the max voltage these panels will provide.

Appreciate the input as it is slowly making sense.

You won't be switching between anything. They are all connected all the time. Your panels are like buckets collecting rainwater, you're just trying to arrange them to collect the most cumulative harvest throughout a day.

[PNPmacnab]

At that open circuit voltage for the controller, it is probably a FAKE MPPT. You said it was cheap. I like camp systems because they get you so close to the energy where you have to actually plan the use. I turn excess PV into hot water and run what I can directly from solar panels. The other day my hot water tanks had turned off, did a load of dishes in the dishwasher with heated dry, did two loads of laundry with high capacity LG washer running off solar panels, Fridge does not run at night so it has to recover in the morning and the battery gets charged. Also run a pump. All this and before noon. The battery is only a car battery. Amazing what you can do when you get creative and ditch big black box systems.

[Mike90250]

With your charge controller, you can only parallel panels.
Then I would parallel all 4 panels, face 2 SE and face 2 SW
It's unlikely you would exceed more than 30A with this configuration, so a 30A PWM controller should work. 40A would be absolutely safe

[Ho jo]

With Max input controller voltage of 42.
Using 23.2 voc panels x 2 in series 46.4
Seems your only choice is all panels in
parallel. Or a higher voltage controller.

[redbank]

[QUOTE=Mike90250;n418674]

No, first, 4 in series is likely to overvoltage your controller @ 80V



I have looked at the specs of the controller (actually have two). One shows max voltage of input at 18v. One panel spec says max open circuit voltage (Voc) 23.2v and the max power point voltage (vMPP) 18.54. So one panel is actually too big for this controller?

My other controller I have shows max input voltage 42v, so I could run two panels with this controller safely.

If I took your advice and wired two panels in series and face them SE and the other two SW what would be the best way to switch between the two panels? I am assuming I need to create some sort of switch before it reaches the controller so I can limit the max voltage these panels will provide.

Appreciate the input as it is slowly making sense.

[SunEagle]

Push the genstart button on the remote.

Makes sense to me. Thanks

[Mike90250]

If I understand you, 4 panels wired in series will be just as effective as 2 wired in series because one of the 4 could not be getting its share of light therefore restricting the others from charging the battery..

No, first, 4 in series is likely to overvoltage your controller @ 80V

But if you have 4 in series, and shade one, the bypass diodes in the shaded panel are supposed to allow the other 3 panels to work, at the expense of cooking the bypass diodes in the shaded panel. So relying on bypass diodes to solve a known problem, is poor practice and eventually, you will be looking for replacement diodes.

[redbank]

[QUOTE=Mike90250;n418646]Any panels wired in series, need to be aimed in the same direction. Power will be limited to the least illuminated panel

If I understand you, 4 panels wired in series will be just as effective as 2 wired in series because one of the 4 could not be getting its share of light therefore restricting the others from charging the battery..