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Son_of_Norway's avatar
Son_of_Norway
Explorer
Feb 08, 2020

Question about Onan Generator

Something I have never understood about generators (I have an Onan 6.5 Emerald III.) A 12-volt DC battery is used to start the generator, which then produces 120V AC. The battery supplies the energy needed to run the generator, right? So, while the generator is running, does it send a 12-volt DC current back to the battery to keep it charged, or does the generator just continue to drain the battery until the battery no longer has enough voltage to keep it running?

So if the generator drains the battery, then there must be a converter in the circuit to keep the battery charged, just like the alternator on a car engine. OK, I'm no electrical engineer, I just want to be sure that I understand this correctly.

Thanks for your tolerance on this post.
  • MrWizard's avatar
    MrWizard
    Moderator
    Feb 09, 2020
    I think !
    Everything from the 1990's up
    Rv generator depend on the house converter to keep the battery charged and supply the 12v control power, fuel pump etc
    And do not charge the battery
    Earlier models 60s and 70's did have a 12v supply circuit as do residential models
  • fyrflie's avatar
    fyrflie
    Explorer III
    Feb 09, 2020
    My battery for my generator is the same battery that provides power to my coach and receives a charge from the converter/ charger when the generator is running or when plugged into 120v.
  • azrving's avatar
    azrving
    Explorer
    Feb 09, 2020
    The generator has a stator under the flywheel. It produces AC current which is sent to a regulator/rectifier. The rectifier changes the ac current to DC current which charges the DC battery. The regulator portion controls the DC voltage level to the battery.
  • enblethen's avatar
    enblethen
    Nomad
    Feb 09, 2020
    Yes, it sends back a trickle of charge. Main charge comes through the converter battery charger that your coach battery is connected.
  • jdc1's avatar
    jdc1
    Explorer II
    Feb 09, 2020
    Your battery is being charged by the same converter/charger your coach is. That generator battery only starts the generator...it needs no other source to keep it running....like a lawnmower motor.

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