Battery question

[elm3420]

This may be a stupid question, but here we go. If I have a battery that doesn't charge, would that stop the lights in my camper from working. Thanks in advance for the help.

[Harvey51]

It is important to know the state of charge because lead acid batteries are damaged by chronically being discharged below 50%.

It is tricky to measure the % of full charge with a voltmeter. When the battery is charging it will have the voltage of the charger on it, which will be more than 12.6 volts - suggesting it is 100% charged. This awkward situation persists for at least an hour after charging is stopped.

The solution is to install a battery monitor that measures the energy of charging and discharging (amp hrs) and shows the % of full charge all the time.

I have a Cheap battery monitor that works well. Higher quality ones are easier to install and more reliable.

[fj12ryder]

I'm not used to referring to percentage charge, so I'm not sure how that would work. Other guys can help you out there. But if you've had it on the charger you should be able to run the lights and pump long enough to get the job done.

[elm3420]

The battery had an 84% charge earlier when I posted. I took it inside and put it on my battery charger to check to make sure that it was charged. When I hokkup the battery back up to the camper do I check the battery at the terminal?

[fj12ryder]

If you have a bad converter, and no battery charger, then there is no way for your battery to be charged. You'll have a flat battery. You may get some charge if you're hooked up to the tow vehicle, but it will be pretty low.

What voltage does your battery measure at the battery itself?

If you're plugged into shore power, and the converter circuit breaker isn't tripped, and you have no 12v lights, then it's very likely you do indeed have converter issues. I just replaced a WFCO unit a few months ago that created the very problem you're describing.

You need to find the converter, ascertain that it is getting 120v power, and physically check the output of the converter for 12v.

The battery will work fine with a bad converter, but it may be very low on charge because of the above described problem. So you may not have enough voltage to run your pump. Again, check the voltage at the battery with a VOM.

[elm3420]

If I have a good battery, but a bad converter will the battery work the lights and pump. Or does the the battery power also need the converter. The reason I am asking is that I am trying to winterize the camper. I need the pump to run so that I can get the antifreeze pumped into the lines.

[Cydog15]

elm3420 wrote:
Number 1 thank you to everyone that took time to give me some advice on this issue.


Here is where we are at this moment. The battery that I have is a deep cycle 24DCM, 525 MCA, and 140 RC.

I am plugged into shore power. When plugged in the only thing that is working is the microwave which is plugged into a 110v plug. I plugged a lamp into the plugs in the camper and they all worked.

At this point I am thinking I have a converter issue. The converter is a WFCO 3-Stage Converter Model: WF-8955AN W/plastic. I need some direction on what and how to check the converter to see if it needs to be replaced. I do not have much experience with electrical so any help is much appreciated.

Best to call the guys at bestconverter.com but in the mean time, I would measure the voltage on your DC fuse board where the red and white wire land. Should be 13.6 there and all over the board unless it happens to be in the boost mode, then it will be higher. I highly doubt your converter is on a GFI circuit unless some knot head moved there because they don't (converter and GFI) play well together. Never seen one factory connected to GFCI but maybe there is. Good luck and call them, they will set you straight.

[mike-s]

If you're not getting any 12V while plugged in, it's a problem with the converter. And, your battery is drained. As soon as you can, get a charger on the battery. If you're lucky, you can save it. The longer it sits "dead," the more likely it will be ruined. With the charger connected and on, you should also get lights.

Then, worry about getting the converter fixed/replaced.

[BFL13]

You need to confirm the converter is getting 120v input. It might not if it is plugged into an outlet that has its GFCI popped on that outlet circuit. Or the breaker panel with the breaker marked "converter" might be snapped over.

Once you are sure there is 120v to the converter, use your multimeter to see if it has 13.6v at its DC terminals. If not, it is toast.

If no multimeter, disconnect that 12v battery by taking the wires off one of its posts. Do the 12v lights in the RV work? If so the converter has DC output.

[elm3420]

Number 1 thank you to everyone that took time to give me some advice on this issue.


Here is where we are at this moment. The battery that I have is a deep cycle 24DCM, 525 MCA, and 140 RC.

I am plugged into shore power. When plugged in the only thing that is working is the microwave which is plugged into a 110v plug. I plugged a lamp into the plugs in the camper and they all worked.

At this point I am thinking I have a converter issue. The converter is a WFCO 3-Stage Converter Model: WF-8955AN W/plastic. I need some direction on what and how to check the converter to see if it needs to be replaced. I do not have much experience with electrical so any help is much appreciated.

[wa8yxm]

elm3420 wrote:
This may be a stupid question, but here we go. If I have a battery that doesn't charge, would that stop the lights in my camper from working. Thanks in advance for the help.

YES/NO/PERHAPS. those are all correct answers.

1: If not plugged into shore power: YES
1b: If the battery is SHORTED: YES
2: if the battery is "High resistance" and you are Plugged in with a modern converter NO
3: With an older converter PERHAPS

Recommend. Replace battery with a TRUE DEEP CYCLE either a pair of GC-2 or a GC-12 (if you can fit them)

If you have a very old converter (Specifically a Magnetek) UPGRADE IT AS WELL

the GC batteries are "Flooded wet cells" this means you can remove a cap and look at the fluid leve inside the cells. Add DISTILLED WATER to about 1/4 inch below the bottom of the filler tube and check every month till you find out how long they can go without water (mine went 4 years) .

[Cydog15]

Elf,
I you you are plugged into shore power or using a generator, the answer should be no, and your lights should work as well as all other DC circuits. By 2009 as your camper appears to be, all power supplies (converters) were internally filtered and did not require a battery to deliver adequate DC voltage to the distribution panel and DC circuits. If your battery is not receiving charge, either the converter is shot, there is a fuse or short stop (or other brand DC circuit breaker) tripped preventing the DC from reaching your batteries. Many people that keep their RV permanently stationed in one place just remove the battery and it makes since IF you don't have the old style linear type that required a battery for filtering.

[time2roll]

OK now let's deal with reality. Remove the battery or disconnect a cable and plug the main cord into utility power. Do the lights work?

Have you tried charging the battery with a portable charger? Maybe the converter is shot.

[wa8yxm]

The answer is "It depends"
If the battery has a shorted cell or 2. YEs it might
If the battery is HIGH RESISTANCE no it won't so long as you are on shore power
If the battery is Low capacity.. It should not but the lights may go out swiftly if not on shore power.

IN short it all depends on the failure mode of the battery.

In all 3 cases the procedure is the same

Remove battery. Insulate positive lead and check converter (measure voltage) to insure operation.. IF NON_OP repalce converter and battery. If converter working normally replace battery. BUT DO CHECK THE CONVERTER.

OH. If Converter is a magnetek 6300.. UPGRADE to Progressive Dynamics 4600

[dougrainer]

If you have a Converter, the lights will work when plugged into Shore Power. Battery(Bad) or no battery. Some RV's have a 12 volt battery disconnect switch(manual or push button) and if OFF will not operate the interior 12 volts on Shore Power or on Battery. Turn the battery disconnect ON and still have no battery or bad battery and you will have 12 volts on Shore Power. It depends on HOW the battery disconnect is wired. Some are wired so IF the disconnect is OFF, the Power Converter will still supply power to the RV on Shore Power, BUT WILL NOT CHARGE THE BATTERY. Until you turn the disconnect ON. IF you have an Inverter/Charger instead of a Power Converter, then on Shore Power you will have NO 12 volts if you have a dead battery or bad battery. Most Inverter/Chargers will NOT charge a dead battery until you put a short 12 volt excitation voltage to the dead battery usually less than 5 minutes. Inverter/Chargers MUST have a battery to function to charge and supply 12 volts to the RV, even a bad battery. Doug