Batteries losing charge while in storage

[tvfrfireman]

My four six volt AGM batteries are losing there charge while the trailer is parked in storage. I disconnected all the wires from the positive terminal but still find them slowly discharging. In a second compartment I have to more batteries and noticed a wire from the positive terminal that goes directly to the hydraulic pump that is used in the level up system. Could this be draining the batteries? I have the trailer up on all 6 jacks to unweight the tires while it is not in use and am wondering if I should disconnect this wire from my battery. I have a 12 volt disconnect switch but it is down stream from t his hydraulic pump. Thanks for any tips....David

[tvfrfireman]

I almost forgot, thanks so much for your help. I have a meter and am going to do what testing I can before I take the batteries in. I will have to learn how to use the ammeter function first. Thanks again. David

[tvfrfireman]

BFL13 wrote:
Does the OP have an inverter in the mix?

Even with nothing on the batteries at all except the big inverter, I get a good spark at the battery post when doing the inverter's wires. I gather that is the inverter's capacitor(s)

Yes, I have an inverter. I have now separated all the batteries and am going to take them to Les Swab tire center to have them load tested.

[BFL13]

Does the OP have an inverter in the mix?

Even with nothing on the batteries at all except the big inverter, I get a good spark at the battery post when doing the inverter's wires. I gather that is the inverter's capacitor(s)

[MNtundraRet]

You state you have 4 6-volt batteries. That means you have pairs of 6-volt batteries connected in series to form 2 12-volt batteries. These two pairs are then connected in parallel.

When you said you disconnected the batteries, did you just disconnect the cables from charging sources (+) one end of the battery-bank and grounded cables on the (-) post of the battery-bank?

If the four batteries are still left connected to each other by parallel and series connections (typical for batteries using a "disconnect" switch and solenoid) a short from a manufacturing defect on a single cell of any of the four new batteries could cause the problem and ruin all the batteries. The spark you saw when removing a cable on batteries you thought were disconnected from the 12 volt circuit could do this if one had a shorted cell.

Getting all four batteries fully disconnected from each other so that each battery can be charged separately and the voltage monitored with a multi-meter is the only way rule out good batteries from bad. If the batteries should actually check out fine (I suspect NOT!) by holding charge over time, the problem becomes harder.

There would have to be a short from an incorrect connection, or a frayed wire from work done on the RV. It could be anywhere on the circuits in the RV. It take someone who knows how to pull fuses and check the circuits with a multi-meter to finally locate and fix the problem.

[time2roll]

If you will be doing this yourself you will need a meter or at least a test light.

[tvfrfireman]

mena661 wrote:

RJsfishin wrote:
I wonder how many times they were run stone dead, and for how long ??

X2

I have never let them go dead. I charge them with a generator or pull it out of the building and let the solar panels charge them.

[mena661]

RJsfishin wrote:
I wonder how many times they were run stone dead, and for how long ??

X2

[RJsfishin]

Quote:

My four six volt AGM batteries are losing there charge while the trailer is parked in storage. I disconnected all the wires from the positive terminal but still find them slowly discharging.
------------------------------------------------

What part of this are some not understanding ?
Even w/ not being fully charged, there is something wrong w/ the batteries ?? I wonder how many times they were run stone dead, and for how long ??

[MNtundraRet]

The solar panels, if properly installed, should have blocking diodes to keep the batteries from discharging back through the panels when sun cannot reach them.

One, or more. of the panels may be the culprit.

[tvfrfireman]

smkettner wrote:
Spark = something is on. Just a matter of discovery.

The 12 volt switch that supposedly turns off all the power was in the off position. This is a new trailer (1 year old) and am mystified by all this. It has been in the shop almost four months in our first year of ownership. I am having trouble finding competent people to work on it. I could go on for pages with all the stories and will stop here. I can build a house from the ground up but electrical and especially 12 volt I don't have a clue. Maybe I should take it to an auto electric shop as the RV folks damage the outside of our new trailer every time we take it in.

[time2roll]

Spark = something is on. Just a matter of discovery.

[tvfrfireman]

smkettner wrote:
Yes something is draining them or one is bad pulling down the rest.
Full 100% charge and then fully disconnect and separate for testing.
Should hold 12.8+ volts for at least a few weeks.

I read the state of charge three days ago and it was 12.8 and is now 12.3. When I disconnected the negative cables, one threw a pretty good spark. This is with everything off.

[time2roll]

Yes something is draining them or one is bad pulling down the rest.
Full 100% charge and then fully disconnect and separate for testing.
Should hold 12.8+ volts for at least a few weeks.

[tenbear]

tvfrfireman wrote:

tenbear wrote:
Time to invest in a clamp-on ammeter and see what the drain is.

I will check into this tool. I am pretty sure that the drain must be the hydraulic system as one other person with same brand has the same problem on the DRV forum. The only thing hooked to the battery is the hydraulic system. I don't understand why so many things are wired upstream of the 12 volt cut off switch.. Thanks for you response..

I should have mentioned, be sure you get one that measures DC current. Less expensive ones may only measure AC current.

[tvfrfireman]

tenbear wrote:
Time to invest in a clamp-on ammeter and see what the drain is.

I will check into this tool. I am pretty sure that the drain must be the hydraulic system as one other person with same brand has the same problem on the DRV forum. The only thing hooked to the battery is the hydraulic system. I don't understand why so many things are wired upstream of the 12 volt cut off switch.. Thanks for you response..