Battery charging issue resolved, perhaps

1. Measurements -- I reported "With external power and the battery disconnect switch in "use" position, there's 7.8V coming out of the converter into the battery. Same using generator power.In the "store" position, there's 15.7V. " These measurements are taken at the battery position, with the cables disconnected from the battery. This, I thought, would show me the output from the converter. Yes?

2. When the Battery Disconnect switch ( Intellitec BD) js in the "store" position, the electric step still functions. All other 12V systems that I can find are off. Normal?

3. I'll go looking for the fuses associated with the BD unit as msg suggested, check grounds as Snowman suggested, and take readings at the battery with no power. I charged the battery to full at home and let it sit for over 24 hours. It seemed to hold its charge.

4. I'm satisfied that the automatic cutover from shore power to generator is working. Is there any reason why I can't test this using generator power. I can do that in the storage yard, as opposed to driving the thing to a friend's house.

Many thanks for help and patience!

Rich

No, it should be in Use position if you want charging. If your numbers are right, there are one or more problems. Did you read the document I linked to in your other thread, the manual for the Intellitec battery control? Anyway...

Take a voltage reading at the converter in addition to at the battery. Let us know what you find. Also, take a battery reading with no power to the RV.

Look for bad negative grounds to the frame, particularly the cables coming off the converter and the battery.

You may also want to double check to make sure your battery disconnect is properly functioning .... some like the intelitec have a couple of fuses on the solenoid and if one goes out it won't operate properly.

I would not want to see any charging voltages for the batteries other than the normal smart mode charger output levels being 14.4VDC-13.6VDC-13.2VDC. Some chargers will produce something in the 15VDC level but only for a few minutes at a time to perform a battery "desulfate" mode. My PD9200 series Converter will do this mode every 21 hours for 15 minutes using 14.4VDC.

Even 13.6VDC will boil battery fluids if left connected for long periods of time...

Measuring my truck alternator DC outputs follow these same DC levels. When I first start up it usually reads 14.2VDC and drops back to around 13.2VDC after a short period of time. This is the DC level I read the most when measuring across the battery with the truck motor running. I like to read 12.6VDC or across the truck battery terminals with the motor turned off...

Any other DC voltages measured when plugged into shore power or running from the generator is most likely due to malfunction of the converter or bad connections associated with battery cables or switch/relay operations.

Just some of my thoughts here
Roy Ken

With shore power connected and battery disconnect in the "store" "off" "disconnected" position, the battery will NOT charge. With switch in the "use" or "on" position, if you are getting 7.8 volts, as Shadow Catcher said, you have a bad converter.

You have a malfunctioning converter! 15.7 V will boil the battery. My bet is that it is a Magnitec/Paralax converter, replace head unit with a Progressive Dynamics.