Author Topic: Voltage fluctuation  (Read 6229 times)

215

  • Guest
Voltage fluctuation
« on: August 01, 2011, 05:51:33 PM »
After driving for several hours my volt meter will start a dance between 12 and 15 volts.  The Aladdin will show a discharge state for less then a minute and then will go back charging again.  The interior DC light's intensity will fash up and down.  I am towing using the Unified Tow Brake braking system which charges the TOAD battery from the coach alternator.  Should I be concerned about this and can anyone suggest what the problem may be.

Gerald Farris

  • Guest
Re: Voltage fluctuation
« Reply #1 on: August 01, 2011, 09:58:52 PM »
Dennis,
From your description, it sounds like you either have a short or a defective alternator. The highest probability for a short would be in the wiring going to the toad unless it was fused to protect the wiring. If you can disconnect the toad brake wiring without disconnecting the lights on the toad, that would be an easy test to see if towing without that wiring connected stopped the problem.

Otherwise the problem will probably get worse, and you will need to correct it. If you can come up with a better description of when the problem occurs and under what conditions someone may be able to offer you more help.

Gerald

Jeremy Parrett

  • Guest
Re: Voltage fluctuation
« Reply #2 on: August 10, 2011, 01:59:19 AM »
Check your starting batteries and thier connections. We had the same  problem and solved it with new start batteries and clean connections. Before we isolated the cause we had switched alternators and still had the fluctuations.  With new start batteries the needle is now rock steady at  14.4 volts.

215

  • Guest
Re: Voltage fluctuation
« Reply #3 on: August 10, 2011, 03:33:10 PM »
Thanks for the suggestion, but I installed new chassis batteries last fall and new AGM house batteries this spring.  It appears that the inverter does not charge the house batteries while driving with the generator running, but that the alternator is charging both chassis and house.  I found that the BIRD does not have a wire to the generator terminal and I cannot locate a loose wire that should be connected.  The directions for the Bird state that a signal from the generator would islolate the two battery banks.  I wonder why Monaco did not wire this in?

Richard And Babs Ames

  • Guest
Re: Voltage fluctuation
« Reply #4 on: August 10, 2011, 03:48:54 PM »
House batteries are charged from shore power or the generator through the inverter charger. Does the inverter charge the house batteries when plugged into shore power?

215

  • Guest
Re: Voltage fluctuation
« Reply #5 on: August 10, 2011, 07:03:07 PM »
Yes the house batteries are charged by the inverter when hooked to shore power.  Under shore power the remote panel goes to Float at 13.8 as required by the AGM's.  Underway, with generaltor running, the remote panel for the inverter shows float charging but the Aladdin shows house voltage at 14.1 and high amp charging if the house batteries were not fully charged when starting the engine.  It seems that once the batteries are fully charged underway, the Aladdin will show the fluctuating charge, discharge scenario.  Thanks for your help.