Solar shutoff switch?

[wordsmyth]

Post-Covid and post Covid-stroke, I am finding this still new to me travel trailer makes for an interesting retirement focus of activity. I certainly need the challenge, but the nature of the beast gives rise to lots of time sitting and looking and thinking while sipping something.

The upshot us that I have an increasing list of questions to drive mining of the information at the various boards on this forum. Thanks as always to those of you who constitute the brain trust. Now to the topic...

My really big questions have to do with electricity. My knowledge of things electrical are scant, but I do know that if I accidentally let all of the smoke out of the system, it tells me I have just created big problems!

About the solar panel and keeping the battery charged -

I want to avoid cooking the battery. Did that once years ago on a motorcycle battery, because the old-school trickle charger didn't shut off (at full charge) like the newer ones do.

So (1) how can I tell if the onboard trickle charger shuts off automatically?

And (2) (assuming it does not), what are my options for adding a manual shutoff so the trickle charger does not fry the battery in my travel trailer?

Direction, information, genuine wisdom, and/or links to videos will be appreciated.

Thanks in advance,

Rick

[Dbunke]

Modern solar controllers are built like most modern battery chargers and are smart enough to trickle and maintain without cooking the battery. Find out what model you have and look up a manual for info. I put a manual breaker between my panels and controller. This allows me to turn off the panels when needed without disconnecting wires.

[wordsmyth]

Originally Posted by Dbunke

Modern solar controllers are built like most modern battery chargers and are smart enough to trickle and maintain without cooking the battery. Find out what model you have and look up a manual for info. I put a manual breaker between my panels and controller. This allows me to turn off the panels when needed without disconnecting wires.

Thanks. I'll look into this pronto.

[Yooper906]

Originally Posted by wordsmyth

Thanks. I'll look into this pronto.

As far as a solar cut off switch, you aren't going to find one on the go pro systems that Jayco installs. To verify this when talking to Jayco on the phone, I disconnected the batteries, disconnected the shore power, disconnected from the truck. I still had lighting and a few functions inside the trailer. Got back from Utah, took it into my dealer and described what was happening. He said that's impossible. So I had him try it. Guess it's very possible.

He called his dealer line to Jayco, Jayco dealer tech rep verified there is NO solar cutoff or switch. So anyone that wants to completely disconnect solar power is going to have to manually disconnect the cables from where they enter the battery compartment from the solar panels.

This is on a 2022 28.5 rsts.

BTW, I'm registering 13.6 V from the battery cables that I had disconnected.

[RogerR]

Just finished installing 200 watts of solar, MPPT controller, fuses, switches and a new lithium battery.
In Renogy installation instructions for the MPPT controller it states that you should never have the solar attached to the MPPT without a battery.

I installed a switch on the positive leg from by solar panels to the MPPT. I added a second from the battery to the RV internal positive line to isolate my battery during long term storage.

Check with your controller manufacturer on what they advise.

[Yooper906]

Originally Posted by RogerR

Just finished installing 200 watts of solar, MPPT controller, fuses, switches and a new lithium battery.
In Renogy installation instructions for the MPPT controller it states that you should never have the solar attached to the MPPT without a battery.

I installed a switch on the positive leg from by solar panels to the MPPT. I added a second from the battery to the RV internal positive line to isolate my battery during long term storage.

Check with your controller manufacturer on what they advise.

Thanks Roger, this is what I'm doing now. Putting a switch on the positive leg from the solar to the controller. Strange there was nothing in the manuals about disconnecting the solar. And nothing about leaving the solar connected without a battery.You have helped a lot, thanks.

[RogerR]

I read the manual and while online asked a tech at Renogy and he replied that yes, you need a shutoff as the MPPT may overheat if no load or battery resistance.

Your brand may operate differently, so I would check your manual or MFG.

To me, there is always the possibility of sparking if left on and you do wiring or battery maintenance.

[bdreinv]

We found out by trial and error its better to check fluid level once a month. We forgot for several and toasted are batteries! Replacing two this weekend! Thanks

[Jeffp60]

Do not unplug the solar panels from the battery terminal during daytime. It will arc.. Wait until it is evening just to be safe. The panels will always have power when the sun is out, so wait for nightfall to disconnect the system

[RogerR]

Originally Posted by bdreinv

We found out by trial and error its better to check fluid level once a month. We forgot for several and toasted are batteries! Replacing two this weekend! Thanks

I decided to go lithium when I found that I could only go one night on a group 27 and about 2 to 3 years before they started to go bad.



I added solar not instead of getting a lithium capable house converter.


Heading to Great Sand Dunes for 4 days no electric to give it the hard test. Temps in 30s at night so a lot of furnace will be used.

[Yooper906]

Originally Posted by RogerR

I decided to go lithium when I found that I could only go one night on a group 27 and about 2 to 3 years before they started to go bad.






Heading to Great Sand Dunes for 4 days no electric to give it the hard test. Temps in 30s at night so a lot of furnace will be used.

Sounds like a great time! Please let us know how the test worked out.