Community Forums

timjet · 03-08-2017, 06:32 PM

Going through my new to me Tradition sitting in my driveway hooked up to electrical power I noticed the chassis batteries are not charging. The house batteries are charging fine but the chassis batteries after sitting in my driveway for 2 days with electrical hooked up are showing 12.0 volts.

I thought the battery charger would charge both the house and chassis batteries, am I incorrect?

mchero · 03-09-2017, 07:46 AM

You are indeed correct. Their is a solenoid between both chassis and house battery positive posts. When the battery control center sees the chassis batteries getting a charge it "should" energize that solinoid. If you can locate that solenoid it should be warm to the touch. If so it most likely needs replaced. I'm sure others will chime in with more detailed information.
Keep us posted.

timjet · 03-09-2017, 08:47 AM

Thanks mchero. I called Fleetwood and like you said there is a solenoid that switches charging to the chassis batteries when the house batteries are above 13.3 volts. When on shore power the house batteries take priority and when on alternator power (driving) the chassis batts take priority. Fleetwood said the most likely reason the batt charger is not charging the chassis batts is a blown 300 amp fuse. I'm going to check that today.

timjet · 03-09-2017, 12:34 PM

OK, got it working. A call to Fleetwood and a tech walked me through the inverter/charger setup. For some reason the max charge was set to 80%, to low for the house batts to get above the 13.3 volts that will trigger the relay solenoid to charge the chassis batts. The tech walked me through the setup. She had me change it to 90% and it's working like it should.

Cat320 · 03-09-2017, 07:16 PM

There are other things on the Magnum you need to check. 80% is plenty high enough to keep the charge rate above 13.3 and go through to the chassis batteries. If my coach is in storage, with nothing on but the charger, I usually keep the charge rate between 30% and 50%.

timjet · 03-10-2017, 03:57 AM

It's a system I don't totally understand. I'm not exactly sure what charge rate is, but it's possible that the house batteries are not able to store the charge they were able to when new. The coach has 4 105 AH AGM batteries, so a total of 420 amps. The capacity is set to 400 AH on the charger, but I know that is not correct because the batts are a couple of years old and can't hold 400 AH anymore.

Also the chassis batteries (2) are wet cell. The charger is a one bank charger and is set to charge either AGM's or Wet Cell, I'm not sure which. So either the chassis batts or house batts are not being charged correctly (wrong charging schedule).

Any help understanding charge rate is appreciated.

Cat320 · 03-10-2017, 03:07 PM

If you don't have the Operator' Manual for the Magnum...I assume it's a 2812...call the AC 800 back, and they'll email you one and you can print it. It will tell you what all the push buttons and rotary knobs do. As you noted, those folks are really good at the AC tech line. However, really in depth inv/charger questions need to be answered by the Magnum folks. 425-353-8833...they are in Everett, WA...Pacific Time Zone.

One thing to ask them is what setting the Magnum should be on when charging AGMs and wet cells at the same time.

mchero · 03-10-2017, 11:08 PM

AGM and Wet Cells at the same time? I don't think so unless you have two separate chargers.

timjet · 03-12-2017, 07:28 AM

[QUOTE=Cat320;3494973 However, really in depth inv/charger questions need to be answered by the Magnum folks. 425-353-8833...they are in Everett, WA...Pacific Time Zone.

One thing to ask them is what setting the Magnum should be on when charging AGMs and wet cells at the same time.[/QUOTE]

Good advice, I will call them Monday. I do have the manual on the Magnum and it does say what the P/B and knobs do BUT not how to use it or set it up for best performance.

Yes, wet cell and AGM batteries charge at different voltages and different rates. I will ask on Monday how to best manage that.