Adding Auxiliary Battery and Isolator

Electrical & Ignition

  1. Greenpeace For Monaco’s

    Greenpeace For Monaco’s New Member

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    Hi Everyone,

    I do a lot of parades and events with my '76 Royal Monaco. This year I am adding an auxiliary battery and an isolator to power the loudspeakers to not only take the load off of the main battery while driving, but also so I can power them when parked and the car is powered off.

    I want to send 12v power to the isolator only when the car is running in order to maintain both batteries, not during cranking or in the ACC position to completely close off the auxiliary battery from the starting battery when the car is off.

    To accomplish this I am planning on using the wire that formerly powered the Electric Choke Control (disconnected long ago).

    My question is other than extending that wire to reach where the isolator will be located and connecting a ring terminal is there anything else I need to do? It's a fused circuit that is meant to send a constant 12v while the engine is running so I'm thinking not, but wanted to ask in case I am missing something since I am in no way an electrical wiz!

    Thanks in advance

    Brian
     
  2. 67Monaco

    67Monaco Old Man with a Hat

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    The preferred method to charge/isolate batteries these days are 12v dc to dc chargers. Granted they're more money than isolators, and if you already have an isolator well you go with what ya got. however dc to dc is way more efficient.


     
  3. Fury440

    Fury440 Old Fart with a dead Fury FCBO Gold Member

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    Check out the 4x4 off road forums, lots of them install secondary batteries for winching.
     
  4. FURYGT

    FURYGT Senior Member

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    If you use a battery Isolator that is the type that older Motorhomes use they are typically set up to charge the primary battery first and then, when the primary battery is fully charge the isolator switches the charge current over to the secondary battery. There are other, better items on the market to achieve the same thing but they are more expensive.