New Battery Issue

[ElbyJ]

Bought a new Interstate 12V battery (Not a forever battery)for the TT on the 3rd of June to replace one that was totally dead. Hooked it up with a battery cut-off switch that I bought from Camping World. Checked out the new battery and all the lights worked fine. A week later we took out the TT for a four day trip. The day before we left, we did our usual and plugged in our 120V power at home to cool down the refridge before we left the next morning. The trailer (Keystone)has the type of cord where the towing vehicle is supposed to be charging the battery as we drive. Since it was a new battery, my mind was not concerned with it. However, when we arrived at the RV camp (about 6 hours later), I checked the status box for the water tanks and battery (which I always after everything is hooked up and running). The battery status box indicated the battery needed to be charged! Initially I was not concerned with the battery reading since the grey tank gauge was telling me the tank was full after only four hours at the site. I wrote it off as possible sensor issues or a bad status box. However, when we got home and I parked the TT, I checked the battery and found out that the water level in all the cells were extremely low. My question -- did the battery overcharge during the trip or did I get a bogus battery from Interstate?

[2oldman]

ElbyJ wrote:
are we supposed to unhook the battery while we connected to a 120V power source?

Stay plugged in in storage?
Stay plugged in roast batteries?

[ksg5000]

FYI - your on-board OEM battery monitor is practically worthless so don't bother getting concerned about the reading you get from that device.

Did you check the water level of your new battery when you purchased it? When you say the water level was low - how low - were the plates showing? Even the old fashioned single voltage (dumb) converters won't significantly deplete battery water is a week or two but topping off at least once a month is a good idea.

Have the battery tested - it's free - bad cell will result in rapid water depletion.

[ElbyJ]

Yes, I am connecting the correct cable to the negative post. I traced the cable out and made sure it was grounded to the frame of the TT. I am leaning toward a bad battery at this time and I will be taking it back to Interstate today or tomorrow for a check. Of course, I assumed (and that will get you into trouble everytime) that the new battery was full of water when I purchased it. That is something you don't check as you "trust" the sales company.

[RoyB]

I should have to added to the above comments I like to make my measurements using my multimeter at the battery terminals when checking things. With the shore power OFF the battery terminals should read 12.6-7 VDC if fully charged. When I connect the shore power to the trailer then the battery terminals should read 13.6VDC (Unless in a smart-mode charging routine) telling me the converter/charger unit is working and all the connections between the Power Distribution Panel and the battery is good.

Here is a neat DC VOLTAGE verses CHARGE STATE list...


I always go to great extent to "NEVER" let my batteries get below the 50% charge state or around 12.0VDC... I also have this nice homemade panel installed inside my OFF-ROAD POPUP is a good spot to view that tells me my batteries conditions at all times.


All of this adds to us being very successful camping off the power grids...

Just my thoughts again...
Roy Ken

[RoyB]

ELBYJ - you need to check your DC OUTPUT Voltage from your on-board converter/charger. I would use a digital voltmeter from LOWES-WALMART-Any number of auto parts stores and not rely on what the trailer % meter says. These multimeters are very inexpensive and cost from $7-$20. If it only puts out 13.6VDC continuous and is not a smart-mode type converter/charger unit then it may boil out your batteries over time when being charger from your home setup.

A failed converter/charger unit may put out as much a 19VDC I have seen reported on here.

I have found using smart-mode type converter/chargers makes over-charging your connected batteries a non-issue anymore. I still check them on a regular basis however as I can't afford to replace them...

Anytime I read about folks working in the battery terminal areas I always expect the worse that the battery terminals may have been installed in reversed order as this is so easy to do. I always make a mental note that the words "NEG" or the symbol "-" printed on the 12VDC battery case always go to the trailer frame ground connection real close to the battery.

It really stands out to me that your on-board converter/charger unit has boiled out the battery fluids - I have had mine do that in three to four days of charging using a single mode converter/charger.. Once the fluids go below the top of the inside battery cores then self destruction occurs and usually you have to replace the battery.

I never disconnect my battery terminals - My on-board converter/charger charges them when I am on shore power or at home connected to my garage 120VAC. I use my 2KW Honda Generator to be the trailer shore power when camping off the power grid to re-charge my batteries every day around 8AM in the morning for three hours of generator run times.

If I disconnect the battery terminals or switch them OFF using a battery disconnect switch then they will not get re-charged as they should. I did however disconnect the batteries when I still was using the single mode converter/charger for long periods sitting at home until I replaced the converter/charger with a good smart mode charging technology unit. I use the PD9260C converter/charger now for charging my battery bank.

Give us more info on what converter/charger you have installed now.

just my thoughts
Roy Ken

[wa8yxm]

Did you hook the BLACK wire to the negative post?

RVs tend to be wired by electricians, and to an electrician black is hot.

This is why I tell folks to paint the hot wire(s) red before they remove the battery.

NOTE: This does not mean it's not done right on your trailer... Just that you need to be sure.

[ElbyJ]

No, it likely overcharged while you were plugged in at home.

Possible.


Interesting comment from a subscriber. Since we are new at RV'ing, are we supposed to unhook the battery while we connected to a 120V power source?

[ElbyJ]

The battery cutoff is attached to the negative terminal and then the negative battery cable is attached to the cutoff. It uses a bar to open/close the connection. Never really used it except to test it out. Was going to use it when I returned to the storage unit to not drain the battery. When I got back, I removed the cutoff unit and just disconnected the battery cables.

Yes, I think I will take the battery back to Interstate for them to check it out.

[Sea_scape]

You didn't say where you installed the battery cutoff, and whether it was turned on. Before doing anything else, check the cutoff wiring. If in the positive wire and the only connection to the battery post is the break switch, or if in the negative wire, and the switch is in the Off position, you will not charge when towing.

[time2roll]

I would take the entire trailer to the battery shop and let them inspect your work and hear the story. I think you will be getting a new battery under warranty.

[MEXICOWANDERER]

Never assume anything. Take the battery back to Interstate where you bought it. The distributor makes a profit peddling batteries, and yours is under his umbrella. Let him check it out. Hydrometer and load test. If he pronounces it "OK" then you might want to start to look for "issues" on your end.

[2oldman]

ElbyJ wrote:
My question -- did the battery overcharge during the trip or did I get a bogus battery from Interstate?

No, it likely overcharged while you were plugged in at home.

Possible.

[1492]

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