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NEOK's avatar
NEOK
Explorer
Dec 13, 2017

Battery or converter Problem?

I have a Progressive Dynamics (PD4645V) 45 Amp Converter/Charger with Built-In Charge Wizard that's about one year old. I had the camper unplugged from a/c power for about several weeks. When I went into it I realized that the battery disconnect switch had not been disconnected. The only thing that would have been pulling power would have been the propane detector. The batteries were dead, not even enough power to get the disconnect switch to engage to turn on power. I plugged back into a 30 amp power receptacle and left it plugged in for a week. The batteries only read 11 volts on the multimeter now. Even when plugged in to a/c power I only get a reading of 11.0 volts on the multimeter. I know the batteries maybe bad now but shouldn't I get a reading at the battery terminals of at least 13.5 volts with the PD4645 converter/charger plugged in the a/c power?

8 Replies

  • Thanks to everyone who replied. At this point I'm pretty sure the batteries are done for.
  • OK Neok,

    Hang on and pay attention.

    If you deep discharged a battery that is not a true deep discharge, it may have shorted a cell, in that case, the PD4645 may be limiting the charge current to both protect itself and prevent a fire.

    If you unplug from shore power, the terminal at the battery will probably drop fast. If it does, that battery is probably toast.

    Disconnect the battery and then put your meter on the on the 12V buss anywhere. That should be good a good voltage. That means the converter is still good. (PDs are good, but should be checked anyway.)

    If you chose to put a brute force charge on the battery, remove it from the unit first. If it has a shorted cell, things can go bad in a big hurry.

    Matt
  • wa8yxm's avatar
    wa8yxm
    Explorer III
    Are they MARINE/deep cycle or Golf Car (GC-2) DEEP CYCLE

    The latter may recover from a few "OH C**P! deep discharges

    The former.. Not so much

    IF THEY ARE TOAST consider a pair of GC-2 in series For just that reason.
  • When in doubt take the batteries out and put them on battery charger - then take them down to tire dealer and have them load tested. Your batteries might be toast - or maybe it's a simple as your battery disconnect had your batteries off-line when you were connected to shore power.
  • The batteries may not be connected to the inverter due to a relay being turned off.

    Check the output of the inverter at the inverter first then at the battery

    The voltage on the battery may be so low that any relay that is supposed to connect, cannot.
  • Suspect the batteries are toast. I would replace them first. Bad batteries can cause some strange symptoms.
  • enblethen wrote:
    Disconnect battery and see what readings do.
    Do you have three way refer? What is set to?Is it turned off?


    The refrigerator was turned off. I will disconnect the batteries and test again tomorrow.

    Thanks
  • Disconnect battery and see what readings do.
    Do you have three way refer? What is set to?Is it turned off?

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