Battery Charging is Driving Me Nuts!

[Gary Winzenburger]

I'm going nuts over what I'm doing wrong with battery management on our 1997 Marquis. I'm sure you all are getting tired of helping with this, but I need to know! I had our coach winterized and put it in storage without electricity. Reason for this is another story! Anyway, I want to keep the batteries charged, and they forecasted cold temps last night (low 20's), so yesterday I started the motor as well as the generator and turned the Heart Interface on thinking that would charge the batteries. The inverter switch is off. After about 10 minutes, the motor alternator was charging more than normal and the "Overload" indicator on the interface remote was blinking. The DC volts were topped at 14.5 and amps were low at around 20-30. The main, systems monitor was also showing the house batteries were high. What am I doing wrong?
Thanks,
Gary

[George H. Wall]

Check for BAD battery cells. Henry

[Edward Buker]

Gary,

I would run just the generator if you can and use just one charging system. The voltage levels being provided by the alternator may be above the normal charging and regulation values that the Heart operates and charges to when it looks at what the batteries need. If you need to start the engine to get the generator going, do so, let it run for a bit and shut it back down. With the generator and Heart charger on see if the Heart works normally in this mode and if not you will have to have each battery checked to see if you have a bad cell/battery causing the problem. There is some chance that there may be an issue with the Heart charging system but there is no need to go there until you try this all out.

Later Ed

[Dick Simonis]

This is a normal charging voltage for temps in the 30's.  it sounds like the inverter charger is functioning properly and taking the voltage to a higher value than the internal regulator of the engine alternator.  Here is a link to a Xantrex tech bulletin explaining the TVG.

http://www.tekrispower.com/pdfs/xantrex/Batteries%20-%20Temperature%20Compensated%20Charging.pdf

Seeing the high voltage can be a bit startling but it does tell you the temp compensation is working properly.

[Gary Winzenburger]

Thanks everyone, I feel relieved and will keep an eye on it. I'm so thankful for the level of expertise you all have, and willing to share it.
Gary,

[Gary Winzenburger]

As a follow up to the suggestions given earlier on my post, I started the generator to use it alone to charge the batteries before an upcoming cold snap. Everything worked just as Ed advised and to the relief of a working charger as Dick suggested. I also checked the batteries for bad cells, which didn't show any.

Thanks again for all your advise,
Gary

[Gary Winzenburger]

As a follow up on the above issues, I brought the Marquis home yesterday from storage. Everything seems to be working fine, but haven't hooked up water due to freezing temps this week. One item that has me baffled, besides no brake lights, has to do with the running and tail/headlights not being very bright now. It's plugged into shore power and the batteries are charged, so don't know what's going on. Any suggestions? Getting ready to take it in for servicing.
Thanks,
Gary

[Edward Buker]

Gary,

If your coach is wired the same as most others without this modification you may only be getting about 10V at the headlights rather than 12-13V due to voltage drop in the long harness path. This mod bypasses most of that wiring length using added relays in the wiring bay below the drivers seat. There is a section of this video that tells you how to see if this mod will help you or not...give it a check.

http://www.youtube.com/watch?v=fmYyoILEhMY

It could be that there is another issue but more than likely this dim lights issue has been with you and your coach for awhile and you just noticed it.

Later Ed

[Gary Winzenburger]

Thanks Ed. I'll check it once the ice melts and I can get into the coach and bays!!
Gary