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Eric99223 · 11-29-2021, 08:41 PM

As promised, here is my electrical question

When the generator is running, it is draining my chassis battery. It's charging the house at 13.8 but not charging the chassis battery at all (starts from chassis) so my question is where to start the rig is a 31' 92 phoenix by cobra and the generator is a Kohler 4.5ckm21-rv that has 130hrs on it total

Thanks in advance

Eric

twinboat · 11-29-2021, 09:30 PM

Pickup a Cyrix 120 battery combiner and wire it between the house and chassis battery. Don't forget to run a ground wire.

Your other option is to move the generator cable to the house battery.

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Eric99223 · 11-29-2021, 11:13 PM

Is it meant to be that way and not charge the chassis? Won't that allow both batteries to run down?

twinboat · 11-30-2021, 06:33 AM

It may have had a different system that kept the chassis battery charged. Look for a device labeled Lampert L145 or something like that..

OR it may have had the generator connected to the house battery. Some folks move it to the chassis battery so they can run down the house battery dry camping and use the chassis battery to start the generator.

The device I suggested is voltage sensitive. It only connects the batteries together IF there is a charging voltage on one or the other.
When your generator is running and charging the house battery, it connects the chassis battery too, charging that.

When your engine is running and charging your chassis battery, it connects your house batteries, charging them.

Shut either charging source and the combiner opens, like it wasn't there.

Gary RVRoamer · 11-30-2021, 08:48 AM

Not all coaches charge the chassis battery from shore/generator power. If unsure if yours is supposed to do that, you can add a battery combiner such as the Cyrix or the LSL Trik-L-Start. Simple to add and works great.

twinboat · 11-30-2021, 09:46 AM

It's true that not all coaches charge the chassis batteries BUT if the generator is powered by the chassis battery it has to, otherwise you end up with a dead chassis battery.
Most RV generators don't have, or connect, self contained charging systems.

I didn't mention the Trik L Start because it's only a 10 amp device.
It's built to maintane a resting battery and may not cover the load of the running generator power use.

Eric99223 · 11-30-2021, 11:25 PM

Talked to Kohler and they said from the model number it should charge the start battery as well so I guess it's time to bust out the voltmeter amd see what is going on in there

153stars · 12-01-2021, 06:11 AM

My Generac 75d has small separate 12v rectifier circuit board ,just enough output to add more juice back to batt than it uses. IDK to amperage but can't be much by the size of it, maybe a couple amps if I had to guess. The small combiner twin boat shared may be cheaper and faster than a replacement especially if it's part of main board. Before adding my Bluesea MTL-ACR, I just used a car charger camping when on my 3000w gas inv. genny occasionally.

Quote:

Originally Posted by Eric99223

Talked to Kohler and they said from the model number it should charge the start battery as well so I guess it's time to bust out the voltmeter amd see what is going on in there