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brutherb's avatar
brutherb
Explorer
Apr 25, 2018

isolator question

I have an isolator in my rv, 3 posts, top post has multiple wires running to it secong post runs to house, 3rd to start, i am getting charge current through to house batteries and back into coach, but i am not getting charge current through to start bank, but it does when i am running the alternator, but not the charger system but i can see the current at the top post and going through to the house bank, super confused
  • MrWizard's avatar
    MrWizard
    Moderator
    Apr 25, 2018
    Sounds normal
    Diode isolators are used between the alternator and the two battery systems RV and chassis
    It is not set up to charge the chassis engine battery from the rv converter
    As long as both sides charge when the engine is running it is operating correctly
  • RoyB's avatar
    RoyB
    Explorer II
    Apr 25, 2018
    The voltage drop across the DIODE version is not good when you are using SMART MODE chargers. Best to have the solenoid type isolation if you are going to use smart mode charging voltages.

    The differences between 14.4VDC-13.6VDC-13.2VDC gets all muddied up when using diode based isolators. Using smart solenoid relays solves this problem.

    Roy ken
  • ksg5000's avatar
    ksg5000
    Explorer
    Apr 25, 2018
    Isolators are either diode or solenoid based - both can fail. My rig has solenoid isolator - the center plug is connected to ignition and emergency start. When you turn the ignition key it energizes the solenoid allowing it to connect the chassis/coach batteries.

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