Solar panels in parallel.

[bryankloos]

Hi guys,

I’ve posted before on my upgrades to the pop up.

I have a 75/15 that I’d like to over panel with a single full size panel on the rack on the roof.

I also plan to get a suitcase for days when I want to deploy and move around the suitcase.

Neither would be hardwired, but more plug and play when I arrive at the campsites.

I was thinking of maybe a 280 watt panel for the roof, or slightly larger knowing that it will never likely get full sun.

The plan was to then run the suitcase in parallel on cloudy days.

The suitcases are 200 watts.

Would it be appropriate to run both panels in parallel and if so what should I be considering relative to pairing/combinations of panel specs. I will probably updates the mppt down the road to get more out of the panels but I’d like to keep the 75/15 for at least a season or three.

Thoughts?

[TitanMike]

Originally Posted by bryankloos

Hi guys,

I’ve posted before on my upgrades to the pop up.

I have a 75/15 that I’d like to over panel with a single full size panel on the rack on the roof.

I also plan to get a suitcase for days when I want to deploy and move around the suitcase.

Neither would be hardwired, but more plug and play when I arrive at the campsites.

I was thinking of maybe a 280 watt panel for the roof, or slightly larger knowing that it will never likely get full sun.

The plan was to then run the suitcase in parallel on cloudy days.

The suitcases are 200 watts.

Would it be appropriate to run both panels in parallel and if so what should I be considering relative to pairing/combinations of panel specs. I will probably updates the mppt down the road to get more out of the panels but I’d like to keep the 75/15 for at least a season or three.

Thoughts?

The 75/15 controller most likely has a max power capacity of 240 watts or so. Not enough for a 280 watt panel but certainly enough for the suitcase.

I would just use the 75/15 controller for the suitcase if it doesn't come with it's own and a new PWM controller for the 280w panel. Keep it simple.

[PhilFromMaine]

Originally Posted by bryankloos

Hi guys,

I’ve posted before on my upgrades to the pop up.

I have a 75/15 that I’d like to over panel with a single full size panel on the rack on the roof.

I also plan to get a suitcase for days when I want to deploy and move around the suitcase.

Neither would be hardwired, but more plug and play when I arrive at the campsites.

I was thinking of maybe a 280 watt panel for the roof, or slightly larger knowing that it will never likely get full sun.

The plan was to then run the suitcase in parallel on cloudy days.

The suitcases are 200 watts.

Would it be appropriate to run both panels in parallel and if so what should I be considering relative to pairing/combinations of panel specs. I will probably updates the mppt down the road to get more out of the panels but I’d like to keep the 75/15 for at least a season or three.

Thoughts?

The devil is in the details. The specifics could get too complex for this forum format.

Is your 280 panel a 24 volt panel? It isn't very efficient to mix 12 volt panels with 24 volt panels. It is most efficient to only run panels that are nearly similar in specs on the same SCC. I agree with Mike that you should use two different SCCs for your two setups. You can get a decent MPPT for around 100 bucks the last time I checked.

[bryankloos]

Thanks Guys,

I haven't purchased panels yet. As this is a PUP, the batteries are on the tongue of the trailer, and I've moved all the electrical components to the inside, including the BVM, MPPT, Inverter etc. I have an SAE charge port on the outside that leads to the "guts" inside. Because of this, I'd like to keep with a simple single SCC configuration. The batteries are well secured and not easily accessible.

I think I'll get a bigger panel for the roof and use that solely for days when I'm not in complete shade. If I'm under a tree (as we often are) I'll just opt for the suitcase assuming I can chase the sun.

The goal with the bigger roof top panel was to get as much power as I could on the cloudier days.

I understand the complexities of the panel matching given my situation.