Please clarify questions regarding solar controller and battery removal

[RSB]

It's still unclear to me if and how the solar controller must be disconnected when batteries are removed for storage. Our 2024 E17A has the duel 6 volt acid set up with the roof mounted factory solar panel. I've read conflicting articles as whether or not disconnecting the solar charge controller is absolutely necessary when removing the batteries. Does anyone have authoritative information on this subject and if it is indeed necessary, what's the best way to do it?
Thanks in advance for any information and advice.

 

[Centex]

Best practice dictates solar panels should be isolated from the controller before the controller is isolated from the battery (and reverse when re-installing the batteries)

Lacking a disconnect switch between the panels and controller ....

1. Cover the panels to eliminate output (just prevents sparks or inadvertent shorting)
2. Disconnect the panel input wires at the solar controller (label before removing so you know which goes where when time to reinstall)
3. Put insulating tape on the bare wire end as each is removed
4. You can now uncover the panels if you want, no worries covered or uncovered
5. you can now remove the batteries, no worries

Hope that helps.

PS - if this will be an annual chore the process can be simplified by installing an appropriately rated DC switch or breaker between the panels and the controller. Then you can just flip-the-switch before disconnecting the batteries, without the need to temporarily cover the panels to prevent sparks / shorting. This can also be handy if there's other need to disconnect / remove a battery (maintenance, troubleshooting etc)

 

[iamunique127]

To give you a visual idea of the switch Alan described above:

The cable that was originally going to the "Solar +" terminal on the controller was re-routed to one terminal of the switch. I needed to crimp on a terminal lug (see photo below).
Then all I had to do was make a jumper cable to go from the other terminal of the switch to the "Solar +" terminal of the controller. Making that cable was simple. I bought a couple feet of welding cable (#6, I think), crimped on an appropriately sized welding lug/battery terminal end (see below) and connected it to the switch. For my controller the cable end of bare stranded wire is inserted directly under the "Solar +" screw.

 

[RSB]

Thank you both very much for the pertinent and seemingly necessary information. I will now (with confidence) disconnect things and remove the batteries for winter storage.
Perhaps the folks at escape should consider adding this information to the owners manual as I'm sure many folks like myself are unclear or unaware of this procedure.
thanks again, Rich

 

[SRS]

The photo blew shows how I did it. The use of a dual DC break came from videos I watched on Explorists Life website. The use of a Blue Sea 30 amp breaker came from the forum. In my 17A the controller is located in the right dinette bench. I have lithium batteries and I always follow the procedure Allen outlined above. Hope this will help. This setup has made it safe and simple to disconnect solar whenever I work on the electrical system.

 

[Jim Bennett]

I am curious as to why you want to remove batteries for storage. Unless it is kept in dark storage your solar will keep your batteries charged. Before solar I just fully charged the batteries and maybe did a top up mid winter. Never had an issue. None of my friends or family with trailers don't do it either, and we can get cold winter temps here in Calgary.

 

[Centex]

Perhaps the folks at escape should consider adding this information to the owners manual as I'm sure many folks like myself are unclear or unaware of this procedure.

Just FYI, the preferred solar controller connection sequence is often / usually found in the solar controller manual. I know it is for Victron controllers.

 

[Luvnlife-ESC]

My trailer has a breaker or disconnect (not sure but I think it’s a breaker) installed with the Victron package. Will it be sufficient if I needed to disconnect the battery?

 

[Centex]

My trailer has a breaker or disconnect (not sure but I think it’s a breaker) installed with the Victron package. Will it be sufficient if I needed to disconnect the battery?

I'd want to confirm that it is installed between the panels and the controller (follow the wires), but assuming it is, that should do the job (most likely the primary reason it's there).

Please post an update in this thread if you determine that switch / breaker is or is not between the panels and the controller - just to satisfy my curiosity.

 

[Luvnlife-ESC]

Thank you sir!

 

[alanmalk]

I am curious as to why you want to remove batteries for storage. Unless it is kept in dark storage your solar will keep your batteries charged. Before solar I just fully charged the batteries and maybe did a top up mid winter. Never had an issue. None of my friends or family with trailers don't do it either, and we can get cold winter temps here in Calgary.

I will second this question. A fully charged lead-acid battery should withstand exceedingly cold temperatures. I never removed my AGM batteries from the trailer in 7 years here in Denver (low temps down to -15F on a regular basis).

But if you feel the need, one alternative is to throw a blanket over your solar panel before removing the batteries.

I now have Lithium batteries and my first winter I left the solar running with the batteries disconnected. The controller didn't seem to mind. The batteries, rated to -20F(*), didn't seem to suffer as best as I can tell. This winter I finally got around to installing a solar cutoff switch and a battery cutoff switch so electrical winterization now only takes 15 seconds.

(*) I have not seen another lithium battery rated to -20F. I am suspicious of that number, but not so suspicious that I took the batteries out. Last winter we hit -19F officially. Ouch!