Driving with 12V House Battery Bank Disabled

[S.Rodimus]

Still working on getting the generator fixed (See prior post if you're curious....but that's not why I'm here today.

Currently have the generator mostly disassembled in preparation to replace the fuel pump and filter (just can't get one last Torx30 loose -- we've tried everything, so unfortunately gonna have to bring it to a pro). The fuel line has been re-attached and re-clamped so there won't be any leaks at the vice grip (now removed) while driving, and my question today is:

To do this work, we had disconnected the one cable that would allow the 12V house battery bank to output power to the house (and generator), but did not disconnect any cables that would allow the batteries to receive charge from the engine. Is it safe for my electrical system to drive the RV in this state, or do I need to reconnect the 12V bank to the house (and generator) before starting the chassis engine?

(Also, I do have the contact on the generator's Start Solenoid Relay covered with electrical tape, as well as its ground wire -- and all other generator wire harnesses are disconnected. The Control Box is also totally out - it's in a Ziploc bag. So I can't imagine there's any way the generator could accidentally start up -- or somehow create sparks -- even if we did reconnect the 12V house battery bank. Correct?)

[Ray,IN]

This is somewhat confusing to me, so please answer some questions I have. I take it to mean both house/coach battery bank cables are disconnected at the battery bank? Both battery cables are disconnected from the genset also?

If both questions are yes, reconnect the cables at the house/coach battery bank after taping up the cable ends at the genset, any you should be OK. This way the genset is not capable of starting or even turning over.
You can use a stand-alone battery charger to recharge the batteries when parked via an extension cord from the CG electric pedestal , and the drive engine should charge them while driving, IF you have a relay that already performs that function.
The genset charges the battery bank through your converter charger.
Your MH sales brochure: https://www.winnebago.com/Files/Imag...Aspect-bro.pdf


Morich should be along soon to download your wiring schematics and explain further and correct my assumptions.

[S.Rodimus]

Originally Posted by Ray,IN

This is somewhat confusing to me, so please answer some questions I have. I take it to mean both house/coach battery bank cables are disconnected at the battery bank? Both battery cables are disconnected from the genset also?

If both questions are yes, reconnect the cables at the house/coach battery bank after taping up the cable ends at the genset, any you should be OK. This way the genset is not capable of starting or even turning over.
You can use a stand-alone battery charger to recharge the batteries when parked via an extension cord from the CG electric pedestal , and the drive engine should charge them while driving, IF you have a relay that already performs that function.
The genset charges the battery bank through your converter charger.
Your MH sales brochure: https://www.winnebago.com/Files/Imag...Aspect-bro.pdf


Morich should be along soon to download your wiring schematics and explain further and correct my assumptions.

I apologize if I wasn't making much sense. Honestly, I'm not sure what you mean by "both house/coach battery bank cables are disconnected at the battery bank" AND "Both battery cables are disconnected from the genset."

Current configuration is that we disconnected the one cable from the 12V house battery bank that brings power from the 12V house battery bank to the house and to the generator. I assume that the 12V house battery bank (if I start the chassis engine) would still receive a charge -- but the way I have it disconnected, it's certainly (we tested) not providing power to the house or the generator's fuel pump.

Inside the generator itself, the Start Solenoid Relay is disconnected, with the cable and the bolt it connects to both now wrapped in electrical tape. And the main wiring harness is also disconnected. (See attached photo.) The genset's Control Box is also totally out - very separate in a Ziploc bag. I assume all this means there's no way the genset can start and/or cause sparks.

All I really want to know is if my 12V house array will be damaged if I start the chassis engine (to drive the rig to the pro to finish fixing my generator) with it still disconnected from being able to bring power to the house/generator? In other words, if the 12V house battery bank can receive a charge, but isn't connected to actually power the house -- will it get damaged?

I just don't want to reconnect it to drive it to the pro because he's just going to have to disconnect it to do his work anyways. But if I should reconnect it, is my current state of what I have disconnected inside the genset safe to not cause any problems while driving?

I don't want to charge the batteries while driving, just to not damage them.

[S.Rodimus]

UPDATE: We just went ahead and reconnected the house battery. I am going to be confident in the way I have the wires disconnected and secured within the genset, that it's safe to travel. If I am wrong, please do let me know. Thanks!

[dkoldman]

Originally Posted by S.Rodimus

UPDATE: We just went ahead and reconnected the house battery. I am going to be confident in the way I have the wires disconnected and secured within the genset, that it's safe to travel. If I am wrong, please do let me know. Thanks!

I think you are fine as if wrong you have no real risk of damage other than you House battery may not charge while you drive. Even if it doesn't, it would still be no issue because as you claim House disconnected there will be no load.

But for someone really answer your question, they would 1st need to know where or how you disconnected the House. i.e. Disconnect Switch, Fuse and if so which fuse, or did you disconnect the wires on the batteries posts of House?

Also, my belief of what you really want or need to know is to answer your own questions is how your engine charges your house battery. I don't know your coach or wiring but I would assume to be the same or similar. When you start the engine there is relay that triggers a solenoid ( called Trombetta) that connects your House & Chassis batteries together so current from Chassis goes direct to House AUX Start/Emergency Start it is the same relay to allow your house battery to help start the chassis battery. So based on where you disconnected the batteries on the House is key. For me I prefer disconnect the main Fuse right at the batteries. If I do that and engine is running the batteries will not charge.

Note: Your coach could be wired differently that is why the wiring is needed. In some cases the wiring may be wrong because it may have been modified.

To be 100% sure get a voltmeter check house voltage direct on posts. Then go start the engine if it jumps to 14.0vdc it is charging, if stays the same it is not.

[Morich]

My thoughts would be that leaving the coach battery connected to the solenoid that ties it to the alternator for charging would be no problem. If the cable is left on at the battery but disconnected and insulated at the generator, there is no chance of any problem of overcharging , etc.
Even if the cable is left on at both the generator and the battery, there is very, very little chance of anything happening at the generator. The battery voltage would be going to the connection on the generator but it then has to have the generator starter solenoid close before the generator would try to crank or do anything.
But if the coach battery disconnect is turned off, the battery to start the generastor is also cut off there!
That battery power could only go somewhere if the generator start switch was pushed to close the contacts in the starter solenoid. Don't try to start the generator when you have it taken apart? I'm thinking you knew that !!

Solenoid is where coach and chassis battery meet and can connect together. that coach power can go to the battery disconnect switch but if switch is off, it can go no further toward coach stuff nor generator!

[S.Rodimus]

Originally Posted by Morich

Don't try to start the generator when you have it taken apart? I'm thinking you knew that !!

Hahahaha, yes.

Thank you for the replies everyone, and sorry for the initially confusing question. If I could just delete the whole thread to prevent that, I would.

[dkoldman]

Quote:
Originally Posted by Morich View Post
Don't try to start the generator when you have it taken apart? I'm thinking you knew that !!

Originally Posted by S.Rodimus

Hahahaha, yes.

Thank you for the replies everyone, and sorry for the initially confusing question. If I could just delete the whole thread to prevent that, I would.

That statement by Morich may have seen over pre-cautious, but some that are heavy users of an AGS, like us have that type of warning everywhere including around the generator to protect anyone who might be working in it. If you inadvertent turn on or leave in AUTO mode that genny may try to fire up if it gets a call from the controller. We have ours wired to ignition for safety so every time we turn that key on/off it will drop out of AUTO mode. But also if we are traveling and it gets got, my wife with instinctively out AGS in AUTO.

Imagine the RV Owner that brings in RV to an Indoor storage facility, in a hurry to go do something and leaves it in AUTO mode, later that night if it got a call the genny could start and if others are in the building they could be at risk.

[Morich]

We have to be smarter than our toys but it sure is a job to keep up.

I'm currently hating on the new Windows 11 version of Paint! They must hate the world to have changed it to make it this hard to use!

[Ray,IN]

IMO you did the right thing.

[imogenkye]

I need to put on a new fuel pump as well. the house battery is already disconnected somehow, loose wires. Do I need to disconnect the chassis battery cables as well before I change the fuel pump? I have a 1987 Winnie Itasca Suncruiser. tia

[Morich]

We don't get wiring info for that far back, so when in doubt, I go for safety and test the cables before doing much around them. If removing the cable is trouble, I would advise looking at the cable at the generator end to make sure it is dead before getting the wrenches involved.
Gasoline and sparks are just not a good combo, so I make sure.

There's theory that the generator will not start and it likely is cranking off the coach batteries but a few minutes thought and testing is often lots better than theory!

[imogenkye]

coach batteries are not on, there's a loose wire I have to figure out how to put back on, think it's the orange one, grounding wire?? but a multimeter test is a great idea. thank you!! We have a tropical storm coming in, wish I'd gotten it done already.

[Morich]

Yikes! Best of luck on getting out of the way!
We used to love Florida but it has changed so much that we sold out and rarely go back.