Battery Issue When Stored

[Searching_Ut]

Originally Posted by ejagnut

I am curious as to the source of the 1% per day figure. If taken as a linear progression it would only take 50 days to one half discharge. If taken as 1% of the REMAINING charge each day it still would only take 70 days to one half discharge, which I believe is far from reality.

It’s been a few years since I’ve been heavily involved in cap checking and tracking flooded type lead acid batteries, but they haven’t changed much over the years. Self discharge has always been a moving variable with a lot of “It depends”. Self discharge is affected by plate composition, with true deep discharge batteries tending to have higher self discharge rates. Age of the battery makes a fair bit of difference, and temperature can make a huge difference. You can easily hit the 1 percent a day self discharge rate on a deep discharge battery when battery temps exceed something between 80 and 100 degrees. In hot weather batteries deteriorate faster, but they also have significantly higher useable capacity as long as they stay at those higher temps. On the other hand, those folks storing their rig for the winter are probably looking at maybe 3 percent per month self discharge in colder climates, with batteries that have much less useable energy.

[Mark_K5LXP]

Originally Posted by ejagnut

... it was necessary to disconnect the battery if stored for more than a few days,

This doesn't pass the smell test. If this were a "feature" of current campers you'd think you'd be hearing more about it on the forums. My smoke detector is a 9V powered unit but my propane detector is hard wired to the house battery. I just checked and it's marked "12VDC 90mA" and measured it's drawing 70mA at 12.75V. It's got a make, model and manufactured date sticker on the back. I think I would take the time to isolate what's drawing the current in the trailer and if it ends up being one or more of the detectors it might be more practical and just as cost effective to replace them with an efficient one, than having to install a disconnect and living with such a large constant draw when in use.


Mark B.
Albuquerque, NM

[ejagnut]

The plot thickens! So far the only hard data has been current measurement at the battery, over one half amp, and anecdotal information from the dealer, factory and some posters on this forum which strongly suggested smoke/LP/CO detectors as the culprit. I completely removed the CO & Smoke detectors in order to measure the actual current draw to find that they are battery powered and not wired into the trailer 12 volt DC. The LP detector was hard wired (Atwood LP-DOB) with a label stated current draw of 70 ma. This is significant but far from the approx. 500 ma I am measuring at the battery. For comparison my car draws 20 ma with everything off (but the theft alarm not armed). I did not measure the actual current draw of the LP detector as it has pigtail leads soldered directly to the circuit board, and they disappear into a rough hole gouged into the wall panel. The radio (Furrion DV 3100) in the "off" mode still has a display showing the time, but I was unable to find specs that indicate current draw in any mode, and did not measure the current as I would have to dismantle the cabinet.

This led to some frustrating discussions with the dealer and factory. When I asked the factory for an electrical schematic/wiring diagram they informed me that it is policy to not provide customers with any trouble shooting or build information, for the safety of the customers. When I asked the dealer for a schematic I was told I would have to get it from the factory, as the factory did not supply them with electrical info Ironic, as my motorhome manufacturer (Monaco pre bankruptcy) is willing but has no wiring info, has no idea how it was wired.

Rod
Vermont

67 Jaguar E Type
55 MG TF
04 Land Rover
03 Safari/Monaco Zanzibar

[Mark_K5LXP]

Originally Posted by ejagnut

it is policy to not provide customers with any trouble shooting or build information, for the safety of the customers.

Sounds like it's a policy about avoiding liability.

That radio looks like a DIN unit, so you can probably get at it/pull it out from the front if you think doing so might be necessary.

I'd try a divide and conquer approach - pull all the fuses and flip any breakers and see if there's still draw. Then restore one circuit at a time and see which ones contribute draw. Even without a schematic you should be able to isolate it down to a circuit or two and there can only be so many connected devices within a camper.

I still have a small phantom load I haven't identified yet in my RV. When I got it there were a number of devices disconnected so it appears the former owner was trying to track it down too. Nowhere near the draw of yours though but still want to find it.


Mark B.
Albuquerque, NM

[ejagnut]

[QUOTE=Mark_K5LXP;4531762]Sounds like it's a policy about avoiding liability.

That radio looks like a DIN unit, so you can probably get at it/pull it out from the front if you think doing so might be necessary.

I'd try a divide and conquer approach - pull all the fuses and flip any breakers and see if there's still draw.

Mark B.
Albuquerque, NM

Yes , that was the first thing I tried. There are only 3 or 4 fuses, 2 or 3 15 amp and one 30 amp. Removing t he 30 amp dropped the battery current to zero, but as there is no labeling of the fuses that wasn't much help.

Rod

[Searching_Ut]

My last 3 RV’s all drew over half an amp with everything turned off. As I mentioned before, my gas/co detector drew a fair bit. As I recall though I measured that with a dc clam on meter, which sometimes can have a fair margin of error at low currents. The TV on my timber ridge was a dc model powered by the trailer battery. It never turned off completely and always drew a couple tenths of an amp, as did the radio in that rig. My current radio always powers the weather emergency portion and comes on automatically when there is a warning. If you have an inverter, most go into a standby rather than complete shutoff if using a remote on off switch. Believe it or not, even the back up camera on my fifth wheel was always on the way the factory wired it. I mounted a switch on a lamp assembly on my back wall so we could turn it off.

Good luck trying to track it all down. Seems to be the norm on modern rigs.

[Mark_K5LXP]

Originally Posted by ejagnut

Removing t he 30 amp dropped the battery current to zero, but as there is no labeling of the fuses that wasn't much help.

The clue there is what stuff quits with the 30A fuse taken out. If one of those things is the radio then Searching_UT's observation of the WX alert feature is as plausible a reason as any. Maybe there's a menu option to turn that off as a test. If there's a fridge, maybe the light inside is stuck on, or an interior cabinet or storage bay light is on. You'll find it, you've already eliminated half or more possibilities already.

Mark B.
Albuquerque, NM

[Soppy]

If you don't have a "salesman" switch the furnace , fridge, antenna and monitor panel may also draw current even though they appear to be off.