Help - choosing a controller for my solar system

[munger]

We recently purchased a solar ready 2014 Hawk. We've got the pre-installed plugs on the roof and the rear driver side of the camper. I now need to purchase a solar system which will include a controller and panel(s). The camper also has two 12 volt dep cycle batteries on it.

The sky is not the limit here, I'm hoping for something economical, but good enough to get us through a couple days off grid. We are low power users and just want the solar to run our heater, fan, and charge our phones.

We are likely getting a 100W solar panel, and I want to know what controller specs would be appropriate. Am I looking at a 12v/30amp controller? Finally, does anyone have any specific models they recommend for a solar controller?

(My apologies if this specific question has been asked before)

 

[rubberlegs]

Do you also want to charge from the truck alternator?

 

[munger]

We've already hooked into the truck with a 3 way plug. So we're hoping to follow the instructions from these videos:

Hooking up After-Market Solar Panels - Four Wheel Campers

 

[rubberlegs]

We've had good success with the Renogy 30a dual-charge controller, similar to the one that Mr. Ski3pin reported on here. His was the 50a but your power needs sound similar to ours. It only charges at half rate each if you have both solar and the alternator going at the same time. But we don't have solar permanently mounted. We got a 100W flex panel that we use in camp. In low wind situations we put it on top of the roof before popping up, or we place it somewhere in the sun on the ground. In good sun it easily keeps up with our camper, which has all your electrical items plus a fridge. I think the fridge is our main user of power. I suppose if we used the heat or fan a lot, it could be the main user. Lights and charging phones are not a lot of load.

There may be other options that cost less than the Renogy unit. I trust the Ski3pins! So I didn't look any further.

100W at 12 volts is only about 8 amps, and we typically only get maybe 4-5 amps out of our flex panel.

https://www.renogy.com/dcc30s-12v-30a-dual-input-dc-dc-on-board-battery-charger-with-mppt/

 

[Vic Harder]

We recently purchased a solar ready 2014 Hawk. We've got the pre-installed plugs on the roof and the rear driver side of the camper. I now need to purchase a solar system which will include a controller and panel(s). The camper also has two 12 volt dep cycle batteries on it.

The sky is not the limit here, I'm hoping for something economical, but good enough to get us through a couple days off grid. We are low power users and just want the solar to run our heater, fan, and charge our phones.

We are likely getting a 100W solar panel, and I want to know what controller specs would be appropriate. Am I looking at a 12v/30amp controller? Finally, does anyone have any specific models they recommend for a solar controller?

(My apologies if this specific question has been asked before)

If you want a lot of background info, check out my build threads (in the signature block if you are using a web browser).

You mention you have two 12v deep cycle batteries. Likely 75AH each if this is a stock install. So you have about 150AH of AGM (lead acid) battery, which is good for 75AH draw before you should recharge (50% SOC).
SOC is where I would start... get a Victron Smart Shunt and install it. It will tell you how much power you use. Without it, you are simply guessing.

And for starters, with 150AH of battery, you want about 2x that in Solar Panels, or 300W. NOT flexible panels. They are generally not reliable.

I like Victron gear, so I would get a Victron 100/30 MPPT to go with that.

Ask questions please....

 

[ckent323]

I second what Vic wrote.

My recommendation is to get the single largest rigid solar panel you can fit on the roof of your camper. Preferably one around 360 W or larger. It will cost around $325. That will be lighter and cheaper than any combination of smaller panels and maximize the ability of keeping your battery charged. I like the Victron Smartsolar 100/30 solar controller it costs about $225.

As Vic wrote to maximize the life of the battery it needs to be fully recharged before discharging every time you use it and it is best not to routinely discharge it below 50%. Install a shunt based battery monitor, such as a victron BVM-712 to know what the state of charge of your battery is. You can buy one for about $195.

I have found after nearly a dozen purchases that PKYS is a good place to buy for both price and service if you have any issues. Also they are knowledgeable and can help with technical questions.

I hop this is helpful.

Craig

 

[Jon R]

Another vote for PKYS here.