Forum Discussion

Its_Hondo's avatar
Its_Hondo
Explorer
Mar 14, 2014

Making 115 VAC Available when mobile

My 2005 Fleetwood Jamboree electrical system allows 115 vac to the outlets -

- When shore power cord is plugged into an outlet
- with the generator running

but not when driving & the generator is off.

This is a factory limitation that I'd like to get around.

There is 145 amps of 12v DC electrical power available from the engine driven alternator. I'm not sure what inverter I have installed, but the previous owner told me that it was upgraded to a "very large capacity" unit a while back.

What would it take to enable the inverter to supply 115 vac when running off of the alternator?
Class C
  • RoyB's avatar
    RoyB
    Explorer II
    Mar 14, 2014
    I am not a big fan of doing things to my truck motor charging system. Too many years of doing just that with my two way radio installs over the years. Always ends up replacing truck items and of course trouble always happens at the worse possible times...

    I would add an inverter system to the trailer battery system to do what you want.

    The truck system is designed to get you back home or go for help not to play with....

    Just my thoughts
    Roy ken
  • Unyalli's avatar
    Unyalli
    Explorer
    Mar 14, 2014
    The question is what 115vac stuff do you want to power from the inverter?

    You might have a 145 amp alternator this does not mean it has 145 amps available. After all the 12 volt stuff in your rig get's it's share and your batteries are full you might have 100 amps.

    -Jeff
  • tenbear's avatar
    tenbear
    Explorer
    Mar 14, 2014
    No one but the previous owner can tell you how the upgraded inverter is wired into the system. You are going to have to look at the wiring to see how it is wired. It shouldn't be too difficult since the 12v wiring should be big short wires.

    You might also consider why it is wired the way it is.
  • bsinmich's avatar
    bsinmich
    Explorer
    Mar 14, 2014
    Simple math says your 145 amps of 12V would translate to 14.5 amps of 120V. That assumes no loss in the inverter and any other draw on the generator. If you put that load on your 145 amp genny all the time it would have a short life and also put a huge load on the belts and engine. Run the generator. They are made for that purpose and last longer when used regularly.
  • bigcitypopo's avatar
    bigcitypopo
    Explorer
    Mar 14, 2014
    I'd Figure out how many amps you need to charge your batteries... How much the inverter draws from your batts...

    upgrade the alternator if needed... and run a set of cables and a bypass switch... just make sure you have a surplus of power to the batteries....

    can't be that hard...
  • BTPO1's avatar
    BTPO1
    Explorer
    Mar 14, 2014
    If you have an inverter in your MH you should have AC voltage available to use. The inverter takes the 12 volt DC from your batteries and changes it to 120 volts AC.

    Some new vehicles do have an AC receptacle for use on them since an alternator does generate AC, then it is run through a rectifier or diodes and changed to DC for use in a 12 volt system. JMT
  • Its_Hondo's avatar
    Its_Hondo
    Explorer
    Mar 14, 2014
    Like I said,I know that I can do that, but that runs up time on the genset, uses fuel and doesn't address what I want to do- have AC available without the generator running by utilizing the alternator if possible.

    Just seems underutilized.
  • BTPO1's avatar
    BTPO1
    Explorer
    Mar 14, 2014
    Why not just run the generator while driving, we do to run the AC. JMT

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