possible dead battery???

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possible dead battery???

Postby afzski » Sun May 13, 2018 8:29 pm

I just pulled my trailer out of storage and put on a battery tender -- three days later - it still shows charging -- battery voltage is 12.8 - but I also changed out my power center to a WFCO WF-8735 unit -- have it all hooked up and the 120V side works well -- and when plugged into shore power - Both the 120 and ALL 12 V circuts appear to work -- I get 14+ v at the battery - But when I turn off the 120V - I do not get the battery to work the lights or the water pump -- Is it possible for a Battery to measure Voltage - but when put under laod - to not work??? even with the tender still connected - the Lights or pump do not work :NC :NC :NC


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Re: possible dead battery???

Postby tony.latham » Sun May 13, 2018 10:27 pm


Let that thing sit overnight (without the charger) and then measure the voltage. If it's well below 12.6 it's more than likely, kaput.


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Re: possible dead battery???

Postby John61CT » Mon May 14, 2018 7:35 am

Measure volts and amps as its charging, disconnected from everything.

Full is when current drops to 1A while V is still over 14, may take 6+ hours if depleted.

Overnight, record voltage, and yes scrap if low.

If it still looks OK, put a 5A load on it, 20 hours per 100A means as new.

should go at least a full day without dropping volts too much.

Otherwise scrap it.
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Re: possible dead battery???

Postby Dale M. » Mon May 14, 2018 7:44 am

Or put meter across battery and turn on all the 12v dc power items and see what battery voltage does (load test).... If it immediately drops below about 11.5 volts its at end of its life, if it stays at about 12 to 12.8 volts for about first couple of hours battery is probably ok.... Batteries have been known to have cells go bad just sitting.... Another issue is how old is battery....

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Re: possible dead battery???

Postby absolutsnwbrdr » Mon May 14, 2018 7:51 am

If its not a sealed battery, check your water levels before you risk any further damage.

Also, the WFCO-8735 have fried more than a few batteries over the years. For a direct replacement, a Progressive Dynamics PD4135 is much more reliable.

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