Inverter Charger Problems

[JR314]

My RV 2004 Winnebago Journey 32T has been in the shop for most of the summer (long story). We’ve been out twice since getting it back and it seems that the batteries are not being charged by the inverter. It could be that the batteries are shot since they are 4 years old, but they seem to take a charge okay from the alternator so I thought I would do some other troubleshooting first.

The inverter/charger appears to be the original Dimensions WIN-12X20B5R1T. In addition to not charging, the remote will not come on at all. There is no display and no error codes or lights. It is completely blank and dark. I unplugged and plugged back in the phone jack connector at the inverter and the remote is still dead. I checked the inverter circuit breaker at the AC panel and it is still on. I checked the fuse in the battery bay and there is equal voltage on both sides. The circuit breaker on the side of the inverter is not tripped. There is pass through power to the AC outlets when plugged into shore power, but as far as I can tell the charger is not coming on. I used to hear a hum from the inverter when first plugged into shore power, but not any more.

I know the shop had the batteries unhooked, so I started by looking at the house battery connections. They all seem tight, but I noticed that there was a black insulated cable attached to the positive terminal on the battery bank. I thought this was odd since positive is typically red. I unhooked the cable and I accidently touched it to the battery tray and it sparked a little. The spark was light and I couldn’t really tell where the cable came from, so I assumed it may be the small, roof top solar battery charger. I ran out of time and hooked it back up that day.

Today, I unhooked the black cable from the positive terminal again and tested the voltage. It was just under 12 volts from the cable. I covered up the solar panel and there was no voltage change. I traced the cable back as best I could. As far as I can tell the black cable goes back to the negative lug on the inverter/charger. Does this make any sense? I don’t know much about inverters, but why would I get voltage out of the negative lug of the inverter? I removed the access panel on the inverter and found that I have about 12 volts coming from both the positive and negative lug of the inverter. Any ideas about why this is happening? Where should I attach the black wire from the negative lug of the inverter? Seems like it should be on the negative terminal of the battery bank, but I’m confused now.

I should also mention that there was no power coming into the coach when I tested it. The shore power was disconnected and the generator was off, and I was still getting 12 volts out of both positive and negative lugs of the inverter.

[creativepart]

Well, this is tough for us to really say.

In general, the inverter/charger is connected positive to positive battery terminal and negative to negative battery terminal. BUT a black cable doesn't necessarily mean that some prior owner didn't just use a black cable because he couldn't find a red one.

It's been commonly reported around here that mid-2000s coaches with older Dimension inverters are having problems charging the house batteries. And, that might be the simplest answer. By the way, Magnum purchased Dimension and will not work on nor repair any Dimension inverter. In their mind you need to replace it.

The wisest place to start is with your house batteries. You need to determine if they are shot or not. None of this guessing will do.

Lastly, find out for sure about your inverter/battery bank wiring and if that means having someone more savvy look over your setup then so be it.

As far as your dealer having your RV for ages - find a good or great independent tech or shop and tell the dealer to pound sand. Let the other pour souls that don't know any better keep filling up the dealer's repair shop.

[JR314]

Thank you for your reply Creative Part. I went back out after the rain stopped and now I am certain that both the positive and negative cables from the inverter/charger were wired to the positive terminal on the battery bank. I'm pretty sure it was done at the shop, but I could never prove it. The electrical was working fine before that though.

I've unhooked everything from the positive side of the battery bank for now. I'm tempted to hook it all back up like I think it should be (positive to positive and negative to negative), but since that negative cable sparked when it grounded, I'm hesitant to try it until I learn more about wiring inverters.

I agree about dealerships. I had it an independent shop and the delay was not their fault. It was a problem with the parts supplier. I'm generally satisfied with the shop though now it's possible they fried my inverter. I'll keep researching inverters and give the shop a call next week.

[Dives2little]

On my Northpoint 5th Wheel, there was always something (vampire circuits) running, so the negative terminals sparked-often quite substantial; big enough spark to make you think that you were cross wiring the connection. Hook the positive up to the positive terminal and then use you meter to check that you aren't running more than 12V through to the negative terminal

[JR314]

Thanks for the input. I had some time and some dry weather last week so I took the cover off the inverter and unhooked the cables from the battery bank. I traced the cables as best I could by hand and then confirmed with a ohm test and continuity test that the black cable does in fact run to the negative lug of the inverter. I charged the battery bank overnight with an external charger, hooked everything up red to positive and black to negative. I plugged into shore power and the inverter came right on and is working fine now. I'm pretty sure at least one battery is toast, but they're 4 year old FLA batteries, so it's pretty much time anyway.

Now to decide if I want to fork over the money for lithium and a new inverter, or stick it out with the FLA and my old inverter.

[FIRE UP]

JR314,
While there has been in the past, some negative comments on the Dimensions 2000 Inverter/Charger, they actually do a fair job, for a number of years. Some had them go out early in life and some, like us, had ours go for over 11 years before we had almost the same exact symptoms as you presently have. Our coach, an '04 Itasca Horizon 36GD with the CAT C-7 330HP. When ours quit, we got lucky. There just happened to be a Magnum 2012ME for sale on Craigslist.

I purchased it and installed it. Oh, and I had to buy a new remote too to control that new(er) Magnum. It's been working flawless ever since I did the install, about 8+ years ago.

At that time, yes, Magnum purchased Dimensions but, they DID work on the Dimensions units at that time. I spoke with a tech at Magnum and he said he's re-build and re-program my Dimensions unit with newer logic and PC boards etc. for a mere $550. I'd already had the Magnum installed when I spoke with him so, I said no thanks and just chucked the Dimensions. The Magnum unit was an almost exact fit other than I had to drill some different holes to bolt it down. No biggie.
Scott