Revolution not charging house batteries from Alternator

[akeyzoo]

OK, So I always assumed things were working as designed until I started reading other threads on this site. Now I think my coach is broken!!
When I arrive at my destination and plug in to shore power I notice my Magnum inverter starts charging my house batteries like crazy, upwards of 90Amps.

Should my house batteries be charging off of the alternator and fully charged upon arrival? If so, how would one begin troubleshooting? I followed the menu in my inverter and nothing stood out as wrong or mis-set. Any ideas?

Chris

[Dukeinhaler]

Chris,
Make sure you do not have a loose battery connection. I had the same thing happen and I had 2 or three loose battery cables. Be careful checking and tightening the lugs. Good luck.

[BFlinn181]

Check and clean all connections. Also, a $10 multimeter can prove if the batteries are being charged. Take a reading with everything off, then start engine and read again. Correct charging will show a voltage increase.

[Old Bounder]

Your rig uses a model of this Battery Control Center. Print it out and follow the trouble shooting instructions.

[akeyzoo]

Many thanks, especially on the troubleshooting guide ya'll


Chris

[pcurt23]

Do you get a low battery warning when you are driving? Your battery charging system has several phases. The first phase is bulk charge. When you first plug into park power the system goes into bulk. Depending on the state of the batteries it may not stay in this phase very long. It will then go into Absorption Charge Mode for a defined length of time. Next is Float Charge Mode and then Battery Saver Mode. (there is also an equalizing mode to re balance the battery bank.) I would look at the battery charge after an hour of so after plugging in to see the state of charge before getting out the tools.

Check your Magnum inverter manual and it will give you all the details.

[Old Bounder]

Originally Posted by pcurt23

Do you get a low battery warning when you are driving? Your battery charging system has several phases. The first phase is bulk charge. When you first plug into park power the system goes into bulk. Depending on the state of the batteries it may not stay in this phase very long. It will then go into Absorption Charge Mode for a defined length of time. Next is Float Charge Mode and then Battery Saver Mode. (there is also an equalizing mode to re balance the battery bank.) I would look at the battery charge after an hour of so after plugging in to see the state of charge before getting out the tools.
Check your Magnum inverter manual and it will give you all the details.

Did you read the topic title?
The problem was NO house battery charging from the alternator. This has nothing to do with the way the onboard charger would charge the batteries.

[Tha_Rooster]

First we're your batteries very low before starting your trip and second how long dis it take you to get there. Your charger always starts with high amps and works it's way down.

[akeyzoo]

I always start my trip from my driveway plugged in and don't use much whilst driving. Certainly an alternator could keep up with my on the road usage.

I am dissapointed with the magnum manual BTW... Didn't find it helpfull in troubleshooting this OR adjusting the max rate at which it charges the house batteries. I would like to slow it down as the batteries can boil over some when I plug in at my destination. That abnormal, or seriously abnormal? Batteries are relatively new and I have topped them off but have yet to check their specific gravity.

Perhaps the BCC is the culprit...

Chris

[BFlinn181]

DID your batteries boil over, or "they can boil over"? Have you checked the voltage at rest and as engine runs? As a couple of posts above point out, the charger starts out at it's highest amp rating and reduces as it detects the needs of the batteries. Unless you have had low battery warnings, dead batteries, or had to add water to batteries, things could be completely normal.

[Old Bounder]

Originally Posted by akeyzoo

I always start my trip from my driveway plugged in and don't use much whilst driving. Certainly an alternator could keep up with my on the road usage.

I am dissapointed with the magnum manual BTW... Didn't find it helpfull in troubleshooting this OR adjusting the max rate at which it charges the house batteries. I would like to slow it down as the batteries can boil over some when I plug in at my destination. That abnormal, or seriously abnormal? Batteries are relatively new and I have topped them off but have yet to check their specific gravity.

Perhaps the BCC is the culprit...

Chris

Just to stay level set, the Magnum charger has nothing to do with charging your house batteries while on the road. All charging would be coming from the alternator, and I understood that (the lack of) to be the original problem. If the house batteries are not being charged from the alternator, then it's a component of the BCC that is causing the problem.

Don't blame the Magnum, or it's manual, for not having a procedure to adjust the charging level. The max (bulk) charge voltage and current are preset, as are the absorption and float levels. It's the battery that determines how much current it needs and will accept.

If you are really having a "boil" problem with that Magnum charger, you need to accurately measure the float voltage from the charger (it should be 13.6 or lower), and have your batteries tested.

The BCC has no function in house battery charging from the Magnum.

Did you find the trouble shooting instructions, that I linked you to, helpful?

[Tha_Rooster]

I'm not a battery expert by no means but I thought if they boil they are toast.

[Old Bounder]

Originally Posted by Tha_Rooster

I'm not a battery expert by no means but I thought if they boil they are toast.

Depends. Boiling is a term generally applied to excessive out gassing. Whether, or not, a battery would be ruined by this depends on how long it is allowed to exist and what the cause was.

If the battery(s) already have a shorted cell, they will boil with even a good charger in use. If it's really the chargers fault, and caught and corrected early enough, damage can be limited.

In any event, "boiling" is not a good thing.

[akeyzoo]

Loulong,
The instructions were great, but I just threw my rig back into storage. Debugging will take a week or so.

I notice that my house batteries often "boil over", if boil over means push out some liquid. It happens to all 4 of my batteries. It happens when the Magnum bulk charges them. The magnum is set to wet cells (forget the precise terminology).

It sounds like this is completely abnormal. I did not purchase my house batteries, the PO did. They are 12V deep cycles, from Napa I believe. They are approximately 18 months old. Could they have been so abused by the PO that now they boil over whenever they take a bulk charge? Is an 80+ Amp charge current when bulk charging typical? I have topped them off with distilled water, but perhaps they are in such bad shape they are a lost cause.

BTW, this still doesn't explain why they appear to not be charging from the alternator, but alas, perhaps I have TWO problems.

Chris