Quick battery discharge.

KenJ

Active Member
Just returned from a short three night get away and was disappointed to find my battery went from what I assumed was a full charge to discharged overnight. I only had a few inside ( two- three ) lights on for a very short period of time, the fridge was on propane, no radio, TV, signal amplifier or CD player was on. I charged the battery with my portable generator directly through the power cable. All monitor light indicated fully charged. Next morning the the reefer check light was on inside lights were dim and monitor lights showed no charge.

Upon returning I had the battery ( 12V Interstate Deep Cycle ) charged and tested. Everything checked out fine. no bad cell. I Think there must be a draw somewhere but I don't know how to test it other than with a multi meter. I'd like to see what is going out of the battery in real time.

Can anyone suggest a solution?
 

JohnDar

Prolifically Gabby Member
The fridge on propane draws power from the battery, as does the LP detector and any digital radio display that is not a plugged in 120V device. And if you left a couple of lights on, they’re drawing 12V, too.
Depending on how hard the fridge had to cycle to maintain temperature, you may have exceeded its capacity.


Sent from my iPhone using Tapatalk
 

Jesstruckn/Jesstalkn

Well-known member
What RV do you have ?
Did you check battery level after Gen was off or unplugged from shore power ?

One trick I have used for checking if there is a draw on my batteries is when I'm hooking them back up with ground wire already connected, touch the positive to the + battery post.

There will be a slight spark if there is a slight draw.
A big spark Big draw.
No spark No draw.

That will give you an idea if you have something pulling power or not...

Right now my guess is your little black button is popped on your 50amp breaker (If you have one) and and your not charging your batteries at all.
 

danemayer

Well-known member
Just returned from a short three night get away and was disappointed to find my battery went from what I assumed was a full charge to discharged overnight. I only had a few inside ( two- three ) lights on for a very short period of time, the fridge was on propane, no radio, TV, signal amplifier or CD player was on. I charged the battery with my portable generator directly through the power cable. All monitor light indicated fully charged. Next morning the the reefer check light was on inside lights were dim and monitor lights showed no charge.

Upon returning I had the battery ( 12V Interstate Deep Cycle ) charged and tested. Everything checked out fine. no bad cell. I Think there must be a draw somewhere but I don't know how to test it other than with a multi meter. I'd like to see what is going out of the battery in real time.

Can anyone suggest a solution?
When you have the shore power cord plugged in to a power source, the Power Converter is running, converting 120V AC into 12V DC to provide power to lights, refrigerator, etc. and to charge the battery.

When you check the battery on the monitor inside, it will show you the output of the Power Converter. So you saw 4 lights, but that didn't necessarily reflect the charge on the battery.

To get a more useful reading on the monitor, shore power/generator power has to be disconnected for 15-20 minutes. Then you'll get an idea of the charge on the battery.
 

GregP

Well-known member
I don't think the parasitic draws mentioned in an earlier post would draw down a good battery overnight. Even the fridge running on propane would be good for a few days or better unless it is one of the old 12volt/propane/AC units, but that is not likely. It sounds more like the battery is not being charged while on shore power or when hooked to the tow vehicle.
 

mlpeloquin

Well-known member
I have learned to never to assume. Did you check the manually reset breaker in the front compartment? It is on line with all the other gray breakers, but it has a small black button. It may have tripped and the battery was not being charged at all. Thus you may have thought you battery was charged, but was not.
 

KenJ

Active Member
I have learned to never to assume. Did you check the manually reset breaker in the front compartment? It is on line with all the other gray breakers, but it has a small black button. It may have tripped and the battery was not being charged at all. Thus you may have thought you battery was charged, but was not.

Thanks,
I was not aware of this reset breaker. I will check it. After charging, the monitor indicated full charge.
 

KenJ

Active Member
I don't think the parasitic draws mentioned in an earlier post would draw down a good battery overnight. Even the fridge running on propane would be good for a few days or better unless it is one of the old 12volt/propane/AC units, but that is not likely. It sounds more like the battery is not being charged while on shore power or when hooked to the tow vehicle.

Thanks GregP,
I agree, I used to get 3-4 nights on one battery although that was on a smaller 5th wheel. Currently I have a 2011 Sundance 2900MK 5th wheel. The fridge is either Gas or Propane. When connected to my portable generator all lights indicate "C" charging. After 2hrs on the generator the top light on the monitor panel goes out and the remaining lights are on. I think that means fully charged. The "C" light is on when hooked to the tow vehicle with the engine running.

- - - Updated - - -

When you have the shore power cord plugged in to a power source, the Power Converter is running, converting 120V AC into 12V DC to provide power to lights, refrigerator, etc. and to charge the battery.

When you check the battery on the monitor inside, it will show you the output of the Power Converter. So you saw 4 lights, but that didn't necessarily reflect the charge on the battery.

To get a more useful reading on the monitor, shore power/generator power has to be disconnected for 15-20 minutes. Then you'll get an idea of the charge on the battery.

Thanks,
Yes after a half hour or so all lights are on.
 

KenJ

Active Member
What RV do you have ?
Did you check battery level after Gen was off or unplugged from shore power ?

One trick I have used for checking if there is a draw on my batteries is when I'm hooking them back up with ground wire already connected, touch the positive to the + battery post.

There will be a slight spark if there is a slight draw.
A big spark Big draw.
No spark No draw.

That will give you an idea if you have something pulling power or not...

Right now my guess is your little black button is popped on your 50amp breaker (If you have one) and and your not charging your batteries at all.

Regarding the size of the spark, assuming I see one, is there a meter of some sort that will allow me to determine the size of the draw?
 

KenJ

Active Member
Take a look at this video.

Thanks so much!!!!!! That video was very informative. I currently have a battery quick disconnect which is used when I store the trailer. When this is in use, I can have the trailer stored for many weeks and still have a full charge. I'm not sure what accessories are in use in the background while I am not using anything whilst boon docking though.

Once again thanks very much.
 

wdk450

Well-known member
Just to ask one more possible question, you weren't using an inverter to make AC power when you were boondocking (not connected to shore utilities when camping)? Some people use an inverter for AC power needs and these inverters use 12 volt current at about a 10:1 ratio (10 amps 12 VDC for every 1 amp 120 volt AC). Also some people forget to turn OFF their charger/converter when using an inverter for power, as the charger/converter would use 120 VAC power derived from the batteries to charge those same batteries. An electronic attempt at a perpetual motion machine.
 

NYSUPstater

Well-known member
I have learned to never to assume. Did you check the manually reset breaker in the front compartment? It is on line with all the other gray breakers, but it has a small black button. It may have tripped and the battery was not being charged at all. Thus you may have thought you battery was charged, but was not.


Even tho I don't have OP's issue, thanks for the reminder cuz I need to replace our slide breakers once I get her out of storage soon.
 

KenJ

Active Member
Just to ask one more possible question, you weren't using an inverter to make AC power when you were boondocking (not connected to shore utilities when camping)? Some people use an inverter for AC power needs and these inverters use 12 volt current at about a 10:1 ratio (10 amps 12 VDC for every 1 amp 120 volt AC). Also some people forget to turn OFF their charger/converter when using an inverter for power, as the charger/converter would use 120 VAC power derived from the batteries to charge those same batteries. An electronic attempt at a perpetual motion machine.

No, I wasn't using an inverter. I was just connected to a 2000W portable generator.
 
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