Question Dead Chassis Batteries in a Few Weeks?

[Joe Hogan]

Another method

 

[Chuggs]

Well...if you guys are right —- a lot has changed since 2016...or perhaps the DSDP is that much different from the VTDP. That could be. Just wonder why the Newmar Engineers would depart from some form of standardized wiring process, for things that are common.

The handout below came in my Black Bag. I have highlighted things that are “Constant Battery Power”. IMPORTANT Note: These are on the HOUSE battery system...not the CHASSIS.

I have a Freightliner Chassis...and according to the EZ-Wiring from the DTNA website...(also attached below) you will see the only thing the Chassis Disconnect does it cut the two 2/0 power lines that terminate under the drivers seat in the basement compartment. So all of those circuits are de-powered. There are other things attached to the two Group 31 batteries not shown in the schematic I attached...so there are things that continue to be connected even with that disconnect switch thrown. There also should be a small red wire with an inline 7.5A fuse...labeled solar. I decided to check mine. It had blown. So for who knows how many years...that 10w ZAMP solar panel hasn‘t done anything but create wind drag. While I had the fuse out...I checked the Voc and it was about 17v open circuit. And attached to the batteries...about 0.3 amps of current going into the batteries. I replaced the fuse...so hopefully it’s doing something now. I’ll check it again when I do my annual service work in February to see if it’s still intact. I’m interested in pulling that solar panel up...to see if I can fish some new wires thru the existing loom. If I can...I’ll remove it and install a 200w panel and SmartSolar MPPT 75/15 controller. Then I know the Chassis Batteries will maintain themselves. It will also make it easier in the future to split my systems for LiFePO4 House Batteries in the far off future.

It seems odd the technician would list three things...that in a lot of coaches are not connected to the chassis batteries at all.

 

[Joe Hogan]

And another way to test for parasitic draw

 

[Chuggs]

I want one

 

[Old-RV'er]

Me too, wonder what will show up if I do that to MH. Gonna have to wait until wx improves. Cold/snow soon.

 

[flyboy013]

I still have a chassis parasitic draw such that the battery will be down to 12.4 in about 3 days. It hasn't been much of a problem since the coach is plugged in nearly 24x7. Reading these posts makes me want to investigate the problem once again. I'll be in warm weather next month and it will give me a good opportunity to tackle the issue again.

Other than using the terminal imaging camera to find a device that's putting off some heat, are there any other good uses for it? Also if the "hot" device in behind the instrument cluster or tucked away somewhere, I would expect the effectiveness of the camera to be someone limited. Figure I'll try the clamp meter along with testing the voltage drop across the fuses.

 

[Joe Hogan]

If you are using a flooded acid battery,

Home 3 - Progressive Dynamics

The Mighty Mini Compact All-In-One System offers an AC/DC Power Distribution Panel and Inteli-Power Converter with Charge Wizard battery charging technology.

www.progressivedyn.com

Search Results​

​

https://www.google.com/search?sourc...hUKEwjjnvnY3YruAhXGrFkKHYoPBIkQ420oAHoECBUQBA


a lead acid battery will self-discharge at a rate of approximately 4% a week. A battery with a 125-amp hour rating would self-discharge at a rate of approximately five amps per week.

 

[Chuggs]

Interesting....

The tech paper put out by Interstate Battery for out GC-2 have charge recommendations per cell. So, wired in series to make 12v you have six cells.

They also use a different temp reference for thier charge parameters than the MS2812 Inverter uses so, I adjusted them.
Magnum



Absorb Voltage 14.51v

Float Voltage 13.43v

Equalization 15.65v

Temp comp...default -5mv/°c/cell

The “Charge Wizard” doesn’t really come close. What they are calling equalization is what the Magnum does everyday when it goes into “Absorb”...