Converter charging vehicle battery

[rooney77]

Is there anyway to tell definitively if when hooked to shore power my converter charges not only the house batteries but the van battery? I haven't found any documentation to tell me it does. I'd like the peace of mind of listening to the radio without worrying about starting the next day.

[Raymond_Quintal]

You do not want to charge both your house batteris and you vehicle batteries at the same time using your converter, you also do you want to charge your dual house batteries if you have them for two reasons. first if one battery is weaker than the other one the converter does not know how to just charge one of them so you will cook (over charge one battery)one battery ruining it while chargeing the other one. The other reason is if one battery is bad and it is connected in any way with the other battery it will cause the other battery to go bad. Never charge both batteries at the same time, I installed a disconnect to both of my batteries I turn one off and charge the other on when its charged I than shut that one off and turn on the other one to charge it. Hope this helps I found this out the hard way after replacing three sets of batteris in a year and a half.

[DrewE]

rooney77 wrote:
I'm not looking to maintain the chassis battery. I want to be able to run the radio without fear of running down the chassis battery. Hence the need for the converter to charge the chassis battery as well as the house batteries. I probably should have stated that in the OP.

If all you're concerned about is radio usage, it shouldn't be too difficult of a job to rewire the radio to be powered from the house battery. The hard part would be running a new wire to it from the DC load center.

Actually, there's a reasonable chance it may already be powered by the house battery. Some makes and models do this, even when the radio is stuck in the dash alongside all sorts of things powered by the chassis electrical system, and I think others have some manner of dual power setup, presumably controlled by the state of the ignition switch.

[pnichols]

rooney77 wrote:
Is there anyway to tell definitively if when hooked to shore power my converter charges not only the house batteries but the van battery? I haven't found any documentation to tell me it does. I'd like the peace of mind of listening to the radio without worrying about starting the next day.

Here's the simplest way to make sure your chassis battery is getting, and kept, charged by the converter when on shore power. Plug the power cord from one of these into a 120 volt outlet in your Class C and plug the 12 volt cord end (it's a long cord) into a receptacle on the dash of the cab - your chassis battery is then getting, and kept, charged whenever you're on hookups. We have been doing this for many years in our Class C and it's Ford chassis battery is at least 5-6 years old:

http://www.northerntool.com/shop/tools/product_200332201_200332201?cm_mmc=Google-pla-_-Automotive-_-...

[pianotuna]

Hi rooney77,

Either jumper across the isolator or use a Trik-l-Start. I chose the trik-l-start myself.

[rooney77]

I'm not looking to maintain the chassis battery. I want to be able to run the radio without fear of running down the chassis battery. Hence the need for the converter to charge the chassis battery as well as the house batteries. I probably should have stated that in the OP.

[Hank85713]

Just go to a parts store and get a solar charger. They run about $50 but no need for a plug in or anything, and you can run the house off wherever you are plugged in. If using a cover or in a barn then a standard battery maintainer is all you need. Sears should have some on sale for the season, I got the 3 amp shaurer for my diesel pickup (2 batteries) and use the 1.5 amps for everything else.

In the rv The front end is out in the sun so I just use a solar charger stuck to the windshield to keep the engine battery charged.

[rooney77]

OK, that makes sense. I'll see if I can find it somewhere.

[Bobbo]

The auxiliary battery switch disconnects the house battery from the house so it won't be drained over time the MH is unused. It also keeps the battery from being charged if plugged in. You will frequently see it referred to on this forum as a battery disconnect switch.

The auxiliary start switch, itself, is neither. However, it powers a massive relay that connects the two batteries together for starting/charging purposes. It is the relay that is powered by the auxiliary start switch that you want.

[rooney77]

Ok, well I was looking through the trik-l-start install instructions and it shows hooking up to a battery isolator. Is that what the "AUX BATT" switch is just inside the house door? Or is that the "AUX START" switch on the dash? I know the "AUX START" switch will allow me to use the house batteries to start the engine but what does the "AUX BATT" switch do?

[2oldman]

valhalla360 wrote:
Before you plug in, take a multi-meter and check the voltage at the battery terminals.Plug in and check again. If it goes up, it is charging.

That's about all there is to it.

[JaxDad]

Bear in mind, if you really only want a trickle charge to the chassis battery all you need is a relatively small gauge wire.

I use about a 6" piece of 12 gauge wire with alligator clips on it to bridge the solenoid.

By adding a third battery to the load on the converter it also lowers the amount of charge each battery gets so I worry less about over-charging them.

I also use a timer on the shore power line when it's parked at home so the batteries are only on charge a few hours a day, not 24 / 7.

[SFVdave]

So putting a a thick jumper across the solenoid will charge the engine battery too? What if your alternator goes out and you onlly have what's left in the engine battery to get you to a garage. Can you either put the jumper across the solenoid or jamb the engine start switch with paper to use house batteries for engine? I suppose then running the generator will keep all batteries charging until you can ge a new alternator.

[Bobbo]

valhalla360 wrote:
Before you plug in, take a multi-meter and check the voltage at the battery terminals.

Plug in and check again. If it goes up, it is charging.

The only iffy part is if fully charged the converter may not put out any power and you won't see the voltage jump (turn on a few 12v lights and it should push the converter to come on)

What valhalla360 said above.

Mine didn't charge the chassis battery, so I installed a Trik-L-Start. Now it does.

One lead to the chassis battery side of the relay that connects the two batteries together, the other lead to the house battery/converter side of the relay, the third lead to ground. You are done.

[rooney77]

eric1514 wrote:

JaxDad wrote:

I think it would be easier to just put a little bit of folded paper under the end of the rocker switch for the Aux. Or Emergency Start switch. That closes the relay and connects the coach and house batteries together via the motorhomes existing internal wiring.

That's very clever and I'm going to look into it. If it works I could see wiring up a permanent on/off switch as a poor man's Trik-l-start.

Agreed. That's a great idea if it'll work.