New Delta 281BH with no solar output.

[GMHunt]

Hi! New to the gang here (about 2 weeks). We’ve been having nasty battery draining issues since we picked up our unit.

First thing I noticed: techs installed the solar leads to the battery on one 6v battery instead of using them in series (so the mppt was trying to charge a 6v battery instead of a 12v)

Luckily it seems like the charge controller isn’t receiving anything from the panel anyway. I get 0.0vdc at the charge controller pv ports but I get approx 44vdc off of the rooftop panel leads.

Does anyone have any idea where the break in the line might be? Inline fuses somewhere?

The + pv line runs through a battery disconnect switch in the pass through storage but it’s working fine (continuity between the two terminals when on)

There’s a butt connector splice behind the electrical panel joining two PV wires together. The splice looks fine but I didn’t pull this one apart to test.

Dealer wants me to bring it in to have a look but they’re booked a number of weeks out and I’d like to use the camper before the snow flies.

Any direction would be fantastic and appreciated!

Geoff in Cold Canada

 

[Oregon_Camper]

First thing I noticed: techs installed the solar leads to the battery on one 6v battery instead of using them in series (so the mppt was trying to charge a 6v battery instead of a 12v)

Lets solve this riddle first. Alliance does not ship RV's with batteries unless you purchase their "Super Solar Package" that come with Lithium batteries. Did you buy this option? If not, then the dealer will always install a low end battery...typically an AGM battery. This leads me to the fact the dealership would be the ones that installed the solar wires incorrectly to your battery. I am confused when you wrote "on one 6v battery" Are you really using a 2x6v battery configuration (in series to get to 12v)

 

[BryanValRox]

Hi! New to the gang here (about 2 weeks). We’ve been having nasty battery draining issues since we picked up our unit.

First thing I noticed: techs installed the solar leads to the battery on one 6v battery instead of using them in series (so the mppt was trying to charge a 6v battery instead of a 12v)

Luckily it seems like the charge controller isn’t receiving anything from the panel anyway. I get 0.0vdc at the charge controller pv ports but I get approx 44vdc off of the rooftop panel leads.

Does anyone have any idea where the break in the line might be? Inline fuses somewhere?

The + pv line runs through a battery disconnect switch in the pass through storage but it’s working fine (continuity between the two terminals when on)

There’s a butt connector splice behind the electrical panel joining two PV wires together. The splice looks fine but I didn’t pull this one apart to test.

Dealer wants me to bring it in to have a look but they’re booked a number of weeks out and I’d like to use the camper before the snow flies.

Any direction would be fantastic and appreciated!

Geoff in Cold Canada

I am a bit confused with the 6 V comments, if in series the system would be 12 volts.
Have you checked your roof top pass thru connection for in-line fuses on the solar lines?
Or a loose connection on the other side of the pass thru?

 

[BryanValRox]

BTW, welcome to the forum!

 

[GMHunt]

Yes on the batteries 2x 6v in series installed at pickup by the dealer.

Wiring after pickup

Battery 1
+ to trailer positive and solar positive
- to battery 2 positive (AND SOLAR CHARGER NEGATIVE)

Battery 2
+ from battery 1 negative
- to trailer negative


I metered the output from the panels on the roof after disconnecting the lines from the inlet. That said, if there are inline fuses in the connection up there I didn’t see them so there may be another climb in my immediate future.

 

[GMHunt]

How do you check the other side of the pass through? Remove and then reseal it after I fix the wires that are likely disconnected? 🤣

 

[Oregon_Camper]

OK...so the dealership did you wrong when connecting the solar to your 2x6v battery setup....that is cleared up

Have you disconnected all the wires from the MPPT controller and see if those are wired backward?

If that all checks out, you will either have to remove the wall (see image) or (crossing fingers) there is access to that area from under the master bed via a false wall under bed?

Taking this wall down is not going to be fun...those water lines will make moving the wall (once unscrewed) difficult.

 

[BryanValRox]

As OC suggested sounds like you have an incorrect hook up. It would be worth checking polarity on those output wires once you figure out your output problem. Sounds like your handy with a meter, so you could disconnect the PV wires at the controller and at the panels and check continuity to see if your problem lies in one or both of the wires.
My guess is a blown in-line fuse or loose connection. Unfortunately, even continuity checking doesn’t guarantee a proper connection. So I would start with validating fuse existence and functionality, and then remove the roof top passthru to access those connections for inspections. Yes you will need to reseal when your issues are resolved.
Also, it sounds like once you have controller output, you will need to re-land those wires to the correct configuration for 12 volts on the battery terminals or a buss , if you haven’t done so already.

 

[GMHunt]

Figured it out. Good old fashioned bad workmanship at the factory. Butt splices not properly crimped (or sized).

They cut a bunch of strands of the 8awg wire out to fit in the wrong size splice and then both positive and negative connections failed. Thank goodness it was one on each side of the splice so the panel didn’t short out. Makes me want to dig deeper and see what other future fires await me.

 

[BryanValRox]

Figured it out. Good old fashioned bad workmanship at the factory. Butt splices not properly crimped (or sized).

They cut a bunch of strands of the 8awg wire out to fit in the wrong size splice and then both positive and negative connections failed. Thank goodness it was one on each side of the splice so the panel didn’t short out. Makes me want to dig deeper and see what other future fires await me.

Congratulations, I see you are handy with a meter! Personally, I love Fluke Products!

 

[KCAlis]

Figured it out. Good old fashioned bad workmanship at the factory. Butt splices not properly crimped (or sized).

They cut a bunch of strands of the 8awg wire out to fit in the wrong size splice and then both positive and negative connections failed. Thank goodness it was one on each side of the splice so the panel didn’t short out. Makes me want to dig deeper and see what other future fires await me.

Had a similar experience with the feed connection to our 12V 20 cuft Furrion fridge in our 2025 310RL. Half the strands were missing and a poorly done crimp allowed the wire to pull free with just a light tug. High resistance/poor capacity = low voltage!

I attribute that poor connection to the eventual failure of the PC board in the fridge and the loss of the fridge’s contents. Glad you were able to find your problem before any harm came of it.