batteries won't charge

[ActorRik]

I hope someone can help.
The batteries in my 2021 Tracer 200 BHS LE don't seem to be taking a charge. I can charge them off the generator (Champion 4500, 30 amp) but not off shore power. That is, connected to the house current, standard receptacle running off a 30 amp breaker, or while towing, off the truck alternator.
When fully charged they will deplete to flat or nearly flat overnight with only the refrigerator on (dry camping) When we got home after the most recent trip, I turned everything off leaving only the propane detector running off the batteries. We plugged into the house power for two days and the batteries took no charge at all.
The batteries are 12v deep cycle from NAPA and are "maintenance free". One is one year old the other is brand new. There is no corrosion on the terminals.
I'm frustrated and confused. I also must confess that I know nothing about DC electrics. Auto electrical systems are like voodoo to me. So I need to keep it simple.
Can someone offer anything to help?

[nvs4602]

Unless they are AGM batteries they are not maintenance free. You can pop the covers off and check the water level..if they are low fill with distilled water to the fill mark, not to the top of holes..

If you have a 12v refrigerator, you probably only have enough batteries to run it over night.

[Aussieguy]

is your generator connected to the main 30amp input of the trailer ?
If yes and the batteries get charged then the trailer's converter (battery charger) is working...

If you then connect to your house and it does not work then the problem will most likely be the house wiring...

check the main breaker in the house

check the power cord with a multi meter OR get a shore power tester to ensure power is connected

Does anything work on shore power (house)?

charging depleted battery with generator or shorepower will take at least overnight (unless lithium)

alternator charging can take much longer especially if you have any loads such as a 12v fridge.

[ActorRik]

Dear AussieGuy,


Let me be a little lazy and cut and paste here.


is your generator connected to the main 30amp input of the trailer ?
If yes and the batteries get charged then the trailer's converter (battery charger) is working...



The answer here is yes


If you then connect to your house and it does not work then the problem will most likely be the house wiring...

check the main breaker in the house



House wiring is working fine, the circuit tests correct, other heavy draw things, like the compressor, run without problems.


check the power cord with a multi meter OR get a shore power tester to ensure power is connected
Does anything work on shore power (house)?


When plugged into shore power, the power cord runs everything in the trailer including the microwave and a/c without problems.

charging depleted battery with generator or shorepower will take at least overnight (unless lithium)



I've left shore power connected for 48 hours


alternator charging can take much longer especially if you have any loads such as a 12v fridge.



Understood. But starting a tow of several hours with the batteries at 2/3 or more gives me absolutely no additional charge, in fact I arrived after that tow with less charge



I've checked the obvious things, like what nvs4602 suggested. (batteries are filled to the correct level.


This is why I'm puzzled


By the way, Thank you Aussie Guy and nvs4602 for responding

[TacomaJoe]

If the batteries charge when plugged into the generator, they should charge when plugged into your house. Everything on the trailer side is the same.

Does your microwave work when plugged into your house?

[Aussieguy]

that makes no sense here too

using the same cord and plug for generator

you need to put a multi meter onto house supply

OR... does the microwave or any other 120v appliance work while connected to house?

once that is done can look elsewhere why the converter won't charge from the house supply


the alternator ...
you can test it by measuring voltage at the battery.
with motor off resting.. should be around 12.6
motor ON and rev it a bit ... about 13.6


If you are at home still get a standard automotive charger and attach it straight to the batteries
get them charged before they sit too long discharged

[Aussieguy]

just re-read some of your replies


a) 2 batteries of different age not the greatest thing to do
disconnect batteries from each other and test the voltage separately


b) noticed you said everything else works when connected
confirm that batteries read 12.6 when NOT connected to house power
and connect to house it reads 13v or more


If it does read over 13v your converter (charger) is working

have the batteries load tested at a automotive parts store

[ActorRik]

Thanks, Aussie guy. The batteries oar within a couple months of each other in age. I can see if they were years apart but one is brand new and one is only a a few months old. Not sure I see now that little separation makes any difference.

[ActorRik]

Follow up on my question.


I broke down and bought two brand new deep cycle batteries. Let's see what happens with these.


Meanwhile, what kind of tester should I get to test them? Every tester I find is geared strictly toward car batteries being used in a car and require the car to be running to read the alternator output. Since these are not connected to an alternator, those testers are not ideally suited to test trailer batteries.

What is the consensus of the forum?


Thanks

Rik

[MR.M]

Originally Posted by ActorRik

Follow up on my question.


I broke down and bought two brand new deep cycle batteries. Let's see what happens with these.


Meanwhile, what kind of tester should I get to test them? Every tester I find is geared strictly toward car batteries being used in a car and require the car to be running to read the alternator output. Since these are not connected to an alternator, those testers are not ideally suited to test trailer batteries.

What is the consensus of the forum?


Thanks

Rik

https://www.amazon.com/Multimeter-Co...29622830&psc=1