Inverter question

The inverter/charger wouldn't charge the batteries since it has no source of 120V power while driving unless the generator is running.

Separately, there's an isolator of some sort that connects the chassis 12V system to the house 12V system when driving to allow the engine alternator to charge the battery. There are a few different designs out there. Many use a high current relay to make the actual connection, and these are a relatively common failure point in the system. (There are other possible failure points, like blown fuses, broken wires, etc.) I would guess that the Magnum Energy panel is not involved in this part of the wiring at all.

1. Acquire a DC volt meter.

2. Set the inverter to Off

3. measure the voltage at the house battery bank, and write down the number.

4. start the engine.

5. measure the voltage at the house bank. If it is higher than the number you wrote down, then the engine is charging the house bank.

prstlk wrote:
We have a 2007 Holiday Rambler DP with an Onan 8500 Generator and an inverter.

The way it is set up through the Magnum Energy panel inside, our batteries do not charge as we are going down the road. The only way to charge them is to start the generator and run it for 2 or 3 hours or plug into shore power.

We called the manufacturer of the panel and they told me that I was to start the coach and go back and look at the panel. If it says “inverting” then it is not charging while the engine is running. This is in fact what it says. He basically told me that some charge while going down the road and some don’t and that it depends on how the MH manufacturer set it up.

Can someone tell me what I would need to do to have the batteries charge while the engine is running and we are moving?

At this point, I'm going to assume that you KNOW for sure that you ARE NOT receiving a charge to your house batteries while the engine is running, that you have checked the ACTUAL VOLTAGE at the batteries and not the panel inside, correct? If not, do so.

About 99.9999999% of the motor homes manufactured in the last 30 years or so, are designed so the engine DOES charge BOTH sets of batteries while the engine is running. I can't possibly imagine a coach manufacturer such as Holiday Rambler, and especially a 2007 model year, not setting up the 12V engine alternator system, to NOT charge both sets of batteries while the engine is running.

As has been stated, there are a few ways that this is accomplished. I am no expert on this stuff but, been around a few dozen coaches and have done a bit of battery work and charging system work. If I may ask, has this condition you're speaking of, ALWAYS been like this or, did it just develope? A suggestion. If it were me, I'd maybe get ahold of another HR owner or, if there's forum of that type, and see what more info you can find on your particular model and year.

About 99.9% of the time, the "Inverter/Charger" has nothing to do with the 12V alternator charging system. It's job is to charge one or both sets of batteries while on shore power, depending on how the system is setup.

So, some analyzing is in order before any major changes or alterations take place.
Scott

What I'm missing here is the "Inverting" comment.. That has nothing to do with the charge process, and is a user select manual button push.

We also have a 2007 made by the same manufacturer, although it is a 2007 Monaco Knight. You don't specify which Holiday Rambler model you have. Our Knight did NOT charge the batteries from the engine running as it came from the factory. I should add that it did say in the manual that it was set up to charge from the engine. When we contacted Monaco we were told that the manual was a misprint and that function was only available on a "high end" coach.

?

2chiefsRus wrote:
We also have a 2007 made by the same manufacturer, although it is a 2007 Monaco Knight. You don't specify which Holiday Rambler model you have. Our Knight did NOT charge the batteries from the engine running as it came from the factory. I should add that it did say in the manual that it was set up to charge from the engine. When we contacted Monaco we were told that the manual was a misprint and that function was only available on a "high end" coach.

ALL MONACO'S CHARGE BOTH BATTERY BANKS FROM THE CHASSIS ENGINE. PERIOD. I don't know where and who some of you talked too, but as a Technician that serviced NEW Monaco's until they went under in 2007(from 1999 when we took them on), and STILL service them all, the system does charge BOTH battery banks from the engine Alternator. NOW, there is one exception. IF you have the Genset ON while driving, the COACH battery charge solenoid from the Chassis Alternator is locked out, because the Inverter/CHARGER will be charging the Coach batteries. Turn the Genset OFF while driving and the Alternator comes back online and charges the coach batteries. Now to the last statement about hi end. That refers to the Trickle charger system that charges the CHASSIS batteries while camped. The lo end Monaco's/HR's did not have that Module installed from the factory. Doug

Enging charging of your house batteries does not involve the Magnum Inverter/converter panel.. It will normally be in INVERTER mode when driving down the road..

how to see if engine is charging batteries method one

You need: A digital volt meter

With engine off, Shore power off, inverter off or on (off is best) measure voltage on the HOUSE batteries..

Start engine, wait one minute, Now re-check the voltage on house batteries

12.6 = Full, Resting. 13+ = Charging. (also full or near full)

NOTE: if the starting voltage is LESS than 12.6.. then any increase = charging.

dougrainer wrote:

2chiefsRus wrote:
We also have a 2007 made by the same manufacturer, although it is a 2007 Monaco Knight. You don't specify which Holiday Rambler model you have. Our Knight did NOT charge the batteries from the engine running as it came from the factory. I should add that it did say in the manual that it was set up to charge from the engine. When we contacted Monaco we were told that the manual was a misprint and that function was only available on a "high end" coach.

ALL MONACO'S CHARGE BOTH BATTERY BANKS FROM THE CHASSIS ENGINE. PERIOD. I don't know where and who some of you talked too, but as a Technician that serviced NEW Monaco's until they went under in 2007(from 1999 when we took them on), and STILL service them all, the system does charge BOTH battery banks from the engine Alternator. NOW, there is one exception. IF you have the Genset ON while driving, the COACH battery charge solenoid from the Chassis Alternator is locked out, because the Inverter/CHARGER will be charging the Coach batteries. Turn the Genset OFF while driving and the Alternator comes back online and charges the coach batteries. Now to the last statement about hi end. That refers to the Trickle charger system that charges the CHASSIS batteries while camped. The lo end Monaco's/HR's did not have that Module installed from the factory. Doug

What he said.... :-) My 1999 Endeavor charges both house and chassis batteries from the engine when driving down the road. I added a Battery Tender brand trickle-charger to my chassis battery that keeps it topped off when we are camping or parked in the driveway connected to shore power or when the genset is running. The outlet I plugged it into is the old TV outlet in the front compartment. That outlet gets locked out when the engine is running, so there's no competing charge happening from both the alternator and the Battery Tender.

Jeff,

If the inverter is on, it may be that the engine charging path may not be able to keep up with the load. That would cause the house bank to discharge while driving. That makes it appear as if the alternator doesn't charge the house bank.

Of course, unless special efforts are made, alternator charging is about the starter battery, not the house bank.

SCVJeff wrote:
What I'm missing here is the "Inverting" comment.. That has nothing to do with the charge process, and is a user select manual button push.