How to keep Chassis batteries from dying w/genset on

[pweekly]

Hi all:
I have a 2005 Mandalay 40E and have had many issues of going for a 2 day/2 night tailgating trip with generator running only to have my chassis batteries dead at the end of the trip. Looking at turning chassis batteries to disconnect, I see that my generator appears to be powered by the chassis batteries because if I disconnect that, the genset turns off. So, would an Xantrac echo charger or some type of trickle charge stop the drain on the chassis for a couple of days? Trying to figure this out and I am NOT handy. Thanks all.
Trish

[CA_Traveler]

Buy a $20 voltmeter and check both battery banks for charging on shore/gen and with engine running. As Doug clearly explained shore/gen may/may not charge the chassis battery depending upon the equipment and if it's operational.

[theoldwizard1]

Chad Brooks wrote:
I just purchased a 2006 Mandalay 40E a week ago. I had the exact same thing happen to me today. I "assumed" it was due to me leaving the inverter on for the whole trip.

Repeating ... Replace you converter/charge with a invert/charger/automatic transfer switch. Most of these have an input for shore power and a separate input for generator power (some with generator auto start).

Hook all A/C load directly to the output of your inverter (EXCEPTION - 2 A/C units)

Hook your DC distribution/fuse box directly to your chassis battery bank.

Never worry again about are the batteries charging, is the inverter on or off, etc.

[dougrainer]

Chad Brooks wrote:
i just went out and disconnected the shore power and fired the generator. After a few seconds it showed on the display panel the inverter/converter was charging(as it was on shore power). One other issue I noticed was the lights sort of flickering when I first connected to shore power for a few seconds then I heard a "click" and they burned steady. If the max shore amps was set at 30amps and the inverter was on, would the inverter make up the difference using the house batteries if I were pulling over 30amps? That was my initial thinking, but I may be misunderstanding the operation of that setting. Everything I have checked seems to be working as it should, I even kept notice of the flashing LED on the inverter as it went through the charging stages.

The AMP setting on the Inverter panel has nothing to do with your shore Power supply. That said, it kind of does make a difference. What the AMP selection means is simple. If you select 30 amp, that tells the Inverter--The CHARGER section to use MAX power to charge the batteries. That means the Inverter/Charger will pull from 11 to 13 amps AC current to charge the batteries faster(Bulk Charge). By setting a lower threshold--10 to 15, the Charger will pull less amps AC but will take 2 to 3 times as long to fully charge the Coach batteries. You would set a lower amp rate if you were connecting to a 30 amp Power source. Leave it at 30 if on Genset or you always use 50 amp shore power. Doug

[Chad_Brooks]

MrWizard wrote:
just replaced them !!

you have a connection/cabling problem

And you were 100% correct! thank you

[Chad_Brooks]

Found the problem! Thanks for all your help. I went to check the generator breaker, slide it out and the breaker was not flipped, I tried to pull the generator back in and got just a "buzz" like a dead battery. Went back with a wrench to double check all of my connections and the main power wire was not quite tight onto the battery (two cables piggy back here and It must have been slightly bound when I installed the new batteries and worked itself loose) Anyway, as soon as I turned the nut I heard the inverter tone change. I went back to run the generator in and it was as strong as you can expect. Like usual, it's a learning experience.

[Chad_Brooks]

i just went out and disconnected the shore power and fired the generator. After a few seconds it showed on the display panel the inverter/converter was charging(as it was on shore power). One other issue I noticed was the lights sort of flickering when I first connected to shore power for a few seconds then I heard a "click" and they burned steady. If the max shore amps was set at 30amps and the inverter was on, would the inverter make up the difference using the house batteries if I were pulling over 30amps? That was my initial thinking, but I may be misunderstanding the operation of that setting. Everything I have checked seems to be working as it should, I even kept notice of the flashing LED on the inverter as it went through the charging stages.

[wa8yxm]

In a properly working motor home or trailer running the Gen-set is identical to plugging into shore power.. With a minor technical difference or two that has no effect on this discussion..

The CONVERTER (or the Charger module of an Inverter/Charger) charges the batteries exactly as it would no shore power.. HOWEVER.......

IF the generator is "out of spec" (Running too fast/slow, voltage too high/low) a good Inverter/Charger may say FOUL and switch from charge to inverter modes.

Your Inverter's display should be telling you stuff. Read it. and report.

Option 2. Tripped circuit breaker generator only powering half of coach, converter in other half.

Option 3: Converter toast.

[MrWizard]

just replaced them !!

you have a connection/cabling problem

[Chad_Brooks]

Hmmm, it's not the batteries. I replaced all 4 Coach batteries this past Thursday. Everything seemed to be fine all weekend, as we were plugged into shore power. Today, I fired up the generator to keep the RV a/c's running. When I got home, I shut everything down. Maybe 30 minutes later, I tried to let a slide out and nothing was happening...everything was dead. The generator would not start either. I fired up the coach to reposition so that I could connect the shore power...everything seems fine now and the batteries are in "float charge" after charging most of the day. Something drained them, but I am not sure what.

[dougrainer]

Chad Brooks wrote:
I just purchased a 2006 Mandalay 40E a week ago. I had the exact same thing happen to me today. I "assumed" it was due to me leaving the inverter on for the whole trip. I was at a campground on shore power for 3 days, unplugged and drove home and my house batteries were dead. After plugging in for just a few minutes, the batteries were back functioning properly. Let me know what you find out, it appears we have the same issue.

1. Inverter is on the COACH batteries, the OP has a chassis battery problem
2. Plugging in to shore power, after a few minutes DID NOT fix your dead batteries. ALL you are experiencing is the Inverter/Charger is now charging the dead coach batteries. It will take 3 to 6 hours on shore to charge the Coach batteries
3. When driving, the Chassis Alternator charges the Coach and chassis battery banks.
4. IF the Coach batteries are boiled dry, then you will have dead batteries and will be running off the Inverter/Charger instead of the batteries. CHECK THE COACH BATTERY WATER. If boiled, they are destroyed, replace them.
5. IF OK, then determine if your chassis charging system is charging the coach batteries. Doug

[Chad_Brooks]

I just purchased a 2006 Mandalay 40E a week ago. I had the exact same thing happen to me today. I "assumed" it was due to me leaving the inverter on for the whole trip. I was at a campground on shore power for 3 days, unplugged and drove home and my house batteries were dead. After plugging in for just a few minutes, the batteries were back functioning properly. Let me know what you find out, it appears we have the same issue.

[turbojimmy]

I doubt the system would have been designed to drain the chassis battery with the generator running. As others have mentioned, you have something not functioning properly.

My generator starts from the house batteries. But my chassis battery was draining due to parasitic draw while stored. It's plugged in 24x7 so I installed a Xantrex Echo Charger:

Echo Charger

It's about $30 more than the Amp-L-Start and frankly I don't know whether it's any better. My Trik-L-Start failed after a year and the manufacturer had a pretty crappy attitude about it. I didn't want to buy anything else from them so I got the Echo. It's been working flawlessly. Chassis battery is always fully charged.

[pianotuna]

Hi,

Another vote for the Amp-L-Start.

http://www.lslproducts.net/ALS_Overview_Page.html

[Mandalay_Parr]

Call me. I can help you.