Best way to Turn off solar while engine is running?

Boatbuilder79

Active member
What is the best way to disconnect my solar charging system when my key is turned on?

Is there a controller with a built in remote?

Could I use a simple relay? Where would I put it? Battery or panel side?
 

Boatbuilder79

Active member
A simple relay controlled by vehicle ignition Will work. Switching the input side of solar controller may be safer for the controller. But ’dunno if thats a problem regardless.

But why ?
Nothing bad happens if solar is always connected.
My voltage regulator will sense the voltage and think the battery’s are charged and not Turn on.
 

john61ct

Adventurer
The voltage on the circuit is a "negotiated" balancing between charge sources and the chemistry / SoC of the battery.

So with a big bank and small source, voltage will remain low until the bank is nearly full anyway.

What model VR do you have? Is it adjustable?

Have you actually measured that scenario happening? Or did someone tell you it would be a problem?
 

DiploStrat

Expedition Leader
Two different campers, one modern, one old, both with solar and engine alternator charging. As a rule, you want all the charge you can get. Never heard of this being a problem.

Good question: Is this a problem you have personally observed on your truck or is this simply something that you have heard?
 

Boatbuilder79

Active member
Truck is a 2015 f150.

I have not added the panel yet but I have had issues with the alternator and the not so smart charging system with both banks. I turned off the trucks battery management system.

I currently have a deep cycle hooked to the trucks battery with a voltage sensing relay. At 13 volts it combines the batteries.

Also, If the house bank is run down in the morning and sun comes up and the solar starts charging and makes the isolator close will the batteries equalize?
 

john61ct

Adventurer
Again, not a problem IRL.

The voltage will not be sufficient to close the VSR until the batt on that side is very high SoC.
 

Borrego60

Rendezvous Conspiracy
Look into an ARC from west marine. I use solar and 2 gp31 batteries. Automatic Charge Relay very easy to hook up. Works with the trucks alternator on both batteries.
 

Borrego60

Rendezvous Conspiracy
I have a Renogy 100watt 1/4 inch in height, never would know it was there on top of my camper shell, running to a controller of course, This goes to my #2 Deka grp31 battery in the bed of the truck,it runs my fridge and other electronics. That is connected to a Blue Seas automatic voltage sensing relay Term #2 and Term# to my starting battery #1 Deka Grp 31.I did have a Painless solenoid, remove that and went with the Blue Seas smart relay. Solar charges all day long and the Blue Seas switches back and forth as needed. System has worked great and never looked back. Even let the truck sit for 3 weeks with radios and fridge running. Got in and started right up!
 

Borrego60

Rendezvous Conspiracy
Just a few ya get the idea. Will try to get a picture of the ARC. You can see the size of cable I run for battery 1,2. The breaker is only there for protection and when I put in the Deka battery the factory cables did not reach with enough slack so the breaker also give me a little more. Question just PM me.

Attachments
 

Boatbuilder79

Active member
Your setup is almost exactly like mine except I have not hooked up the panel yet. What truck do you have and how did you attach your panel to the camper? Did you use screws?

I am using a yandina combiner 160 which is very similar to the blue sea acr. I use a blue sea acr in my boat and they work the same way.

 

Borrego60

Rendezvous Conspiracy
O3 tundra limited.Snug top shell and SS button head screws and lock washers into the fiber glass.
 

FJR Colorado

Explorer
I'm a big fan of discrete solar systems. Separate deep cycle battery fed by solar always connected and completely separate from the vehicle system.

Much easier to put 2nd battery in bed. You always have an emergency battery. Never a worry about drawing down to the point of not starting.

I have a Tundra build thread on this. Of course, this is dependent on 2 factors:
  1. Parking outdoors
  2. Where you live (no issue in sunny CO)
But as many others have said, if you go with a traditional dual batt set-up, no need to disconnect solar that I can think of...
 

john61ct

Adventurer
Yes for those who drive to a site and then sit for weeks, alt input isn't significant overall anyway.

But for those who are doing long drives every 2-3 days, it is the solar that becomes a relatively minor contributor to total Ah input.

But most of us going off grid for long stretches want to have max flexibility, and take advantage of all possible inputs.

A good VSR is not rocket science, nor that expensive.
 
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