How long should battery hold charge

[tim1970]

I had to park my 5th wheel at a neighbors house while I had some dirt work done at my house. It was parked at his house for 5 days without being hooked up to electric. When I went to get it, the battery was completely dead, and I had to hook up the cord to my truck before I could operate the power lift. I didn't utilize the battery disconnect, but there was nothing left on. All lights, water pump, refrig, water heater, etc was all off. Is this normal? This is just the standard 12v battery that came with my unit when I bought it.

[maillemaker]

Why not just utilize the battery disconnect switch and kill all power from the battery. As it's been said there is always parasitic draws.

This is what I did. I went to Harbor Freight and got a pair of battery cut-off switches for the engine and house batteries. Whenever I park the RV I disconnect all the batteries.

The only problem with the Harbor Freight switches is the plastic knobs are not well molded to the brass part of the knob. So you twist the knob and it does not twist the brass part. I drilled through the whole assembly and pressed in a pin.

Steve

[Itinerant1]

tim1970 wrote:
I had to park my 5th wheel at a neighbors house while I had some dirt work done at my house. It was parked at his house for 5 days without being hooked up to electric. When I went to get it, the battery was completely dead, and I had to hook up the cord to my truck before I could operate the power lift. I didn't utilize the battery disconnect, but there was nothing left on. All lights, water pump, refrig, water heater, etc was all off. Is this normal? This is just the standard 12v battery that came with my unit when I bought it.

Why not just utilize the battery disconnect switch and kill all power from the battery. As it's been said there is always parasitic draws.

[RoyB]

Just for comparison I completely disconnect my battery bank on my Starcraft 14 R/T setup which has three 85AH Batteries for my battery bank.

When i quit running the trails in early December I will leave the batteries sitting on my tongue but they are completely disconnected with my Blue Sea Switches. I am usually reading 12.6-7VDC on my battery monitor panel with no DC CURRENT being drawn. I usually keep tabs on thing just out of habit and will watch the battery DC VOLTS just sitting there disconnected...

It very slowly starts dropping off on DC VOLTS and by MARCH when I want to start heading for the woods again they will be down to the 12.4 VDC level. When I see this I will hookup my shore power and start my on-board PD0260C charging again...

It does get down into freezing temps here in VA but had zero problems with my batteries sitting on my trailer tongue all winter long. They do not freeze over if they are holding a decent charge level...

Been doing this since around early 2009 and after loosing one of my four 85AH Interstate batteries early from boiling out fluids due to trying to charge with a single 30A single mode 13.6VDC ELIXIR converter/Charger unit. After I replaced the ELIXIR with the Progressive Dynamics Converter/Charger Smart Mode 60A setup all have been just fine ever since. I still check the fluids levels ever couple of weeks out of habit however...

Roy's image

My three 85AH Interstate started to not holding their their charge state in 2015 and I finally had to stop using them. I am just now getting to the point of building up a new battery bank using two paralleled groups of Duracell 6V 230Ah batteries wired in series. this should give my a big 460AHs 12VDC battery capacity.

Hopefully I will be back on the OFF-ROAD camping trail this season...

Roy Ken

[wnjj]

tim1970 wrote:

DrewE wrote:


Was the breakaway switch for the brakes possibly turned on? A light left on somewhere that's not readily noticeable, like in a storage compartment perhaps? The TV antenna booster?

I didn't realize there was a switch for the breakaway cable. If so, it has been on since I had the camper. Also, wouldn't the TV antenna booster be AC? How much power would it draw anyway?

There’s no extra switch for the breakaway, the breakaway itself is a switch. It would only come in to play if someone pulled it and then your battery would be dead real fast.

The booster is 12V.

Here’s a thread where another guy traced his parasitic loads down at the end. https://www.rv.net/forum/index.cfm/fuseaction/thread/tid/28528175

[tim1970]

DrewE wrote:


Was the breakaway switch for the brakes possibly turned on? A light left on somewhere that's not readily noticeable, like in a storage compartment perhaps? The TV antenna booster?

I didn't realize there was a switch for the breakaway cable. If so, it has been on since I had the camper. Also, wouldn't the TV antenna booster be AC? How much power would it draw anyway?

[DrewE]

I suspect there was some load other than just the propane/co detector and radio memory. Those should not add up to more than a couple hundred milliamps or so, which works out to maybe five or six Ah per day. That certainly is enough to put a dent in a single battery, but should not be enough to make it completely flat assuming it was charged to begin with.

Was the breakaway switch for the brakes possibly turned on? A light left on somewhere that's not readily noticeable, like in a storage compartment perhaps? The TV antenna booster?

[ScottG]

Even when off the stereo is pulling power to keep memory and then of course there's the Propane detector that cannot be turned of without some kind of battery disconnect.

[azrving]

When you believe everything is off test for amp draw. Some multimeters will test amperage draw or use something like a fuse buddy.

[Ski_Pro_3]

When everything is turned off, there could still be other loads. These are referred to as 'Phantom Loads'. You can buy a DC clamp-on amp meter to measure this load. Clamp the positive cable at the battery and start pulling fuses to see what is being supplied power all the time. I found out a rechargeable flashlight I installed in my RV and a charger for a pair of walkie talkies was killing my batteries. DUH!!

Good luck hunting down what's killing the battery!

[tim1970]

The 5th wheel is 1 year old, so I am assuming the battery is not much older. The antenna amplifier was off, but I am not sure about the entertainment system. I would have assumed that was AC only.

Is there a (simple) way I can test the power usage at my house? Obviously, I can unplug when at my house, but is this something I can test with my multi-meter, or am I only able to test how many volts the battery is putting out?

[KD4UPL]

Did you also turn off the stereo, LP leak detector, CO alarm, and TV antenna amplifier? I'd have to assume one or more of those was one. 5 days is a little quick but not necessarily out of the question. How old is the battery? Have you checked the water level lately?

[ScottG]

Was the propane detector and the radio still connected?
They will help drain the battery much fast than if it was disconnected.

[Lynnmor]

A cheap battery won’t last long with detectors, appliance boards and other loads on all the time. Turn off the switch as soon as power is disconnected. Now you took even more life out of the battery by discharging it completely.