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mtofell1's avatar
mtofell1
Explorer
Sep 15, 2017

Convert 120V to 12V

I Just got a macerator to empty tanks at home and am a bit stumped on powering it. I know I can pull right off the battery but am wanting to run it off my house/shore power. Reasons being I have two tank outlets on my 5th wheel so wiring up to both is a hassle. Also, I mainly bought this thing just to avoid lines at dump stations and so if I use my RV at home I can dump. I may wire up the RV at some point but for now I'm just looking for home use.

Anyway, I'm so familiar with house wiring that I'm embarrassed to even be asking these questions. I've installed electric panels in houses and wired too many things to count (I'm a building inspector by trade so I even got all the permits to ensure I did it right :))

So, what I'd love to find is a simple device I could plug into my outlet at home and wire up the two legs of this macerator to. In searching I'm getting confused by all the terms - transformer, inverter, converter - 12V, 24V.

I've got to think the part I need is simple to find but an internet search seems to just turn up inverters (I know what this is and know it's going the wrong way). From what I do understand I think I need a transformer - like for a doorbell, but the 20A rating and wire size on this macerator tell me I need way more than something for a doorbell.

Thanks for any advice.
  • MEXICOWANDERER's avatar
    MEXICOWANDERER
    Explorer
    Sep 15, 2017
    SoundGuy wrote:
    So, to the OP ... why not tell us just which "macerator" you bought so rather than have us all continue to guess we can intelligently discuss how to best power it? :h



    I tend to lose interest after 21 replies go by and this simple question remains ignored.
  • Byrogie's avatar
    Byrogie
    Explorer
    Sep 15, 2017
    I 2 wired a 7 pin plug ($10) and connect to the umbilical. Make it as long as you need to hit both outlets.
  • SoundGuy's avatar
    SoundGuy
    Explorer
    Sep 15, 2017
    So, to the OP ... why not tell us just which "macerator" you bought so rather than have us all continue to guess we can intelligently discuss how to best power it? :h
  • MrWizard's avatar
    MrWizard
    Moderator
    Sep 15, 2017
    Hi I'm not sure a jump box would work
    This is not a (2) minutes rapid drain
    The mace grinds and pumps, it has a set Max flow rate
    20 amps * minutes equal amp minutes
    A (9) amp hr battery pack would have 270 amp minutes to 50% soc
    How long to empty one 40 gal tank?
    He has (2) tanks
    10 minutes per tank would equal 400 amp minutes
    Using 400 out of 540 total equal way below 50% soc
    At that level will a jump box even keep the pump running to completely empty the second tank
  • SoundGuy's avatar
    SoundGuy
    Explorer
    Sep 15, 2017
    mtofell1 wrote:
    I will likely wire this thing into my trailer at some point but just want to be sure it all works the way I want before doing that.


    If we're talking about a FloJet Waste Macerator it works just fine for all the rest of us who own one, why wouldn't it work for you? :h

  • mtofell1's avatar
    mtofell1
    Explorer
    Sep 15, 2017
    Thanks everyone.... auto jump starter makes total sense. I will likely wire this thing into my trailer at some point but just want to be sure it all works the way I want before doing that.
  • Bumpyroad's avatar
    Bumpyroad
    Explorer
    Sep 15, 2017
    my dump station was adjacent to my generator and the 12 volt starter wires were front and center on the gen set and I just ran wire from there back. I use MinKota trolling motor connectors to plug the macerator to the gen set leads.
    bumpy
  • CA_Traveler's avatar
    CA_Traveler
    Explorer III
    Sep 15, 2017
    OP,

    Why not just go ahead and wire the rig? You can use frame ground and one positive wire. Depending upon existing rig wiring the new wire length may be short.

    Now no matter where you dump you have the option of taking and using the macerator.
  • CA_Traveler's avatar
    CA_Traveler
    Explorer III
    Sep 15, 2017
    Sprink-Fitter wrote:
    naturist wrote:
    Do you have shore power at home? Why not just hook into the fiver's existing 12 volt system like it was designed to do and let the existing converter in the trailer do what it was designed to do, i.e. provide 12 volts off shore power?


    They said there are two outlets on the RV so they would have to wire it in two places and they do not want to do that.

    I would use a battery charger
    A single 12V plug and short extension on the macerator would eliminate wiring to 2 plugs.
  • Sprink-Fitter's avatar
    Sprink-Fitter
    Explorer
    Sep 15, 2017
    naturist wrote:
    Do you have shore power at home? Why not just hook into the fiver's existing 12 volt system like it was designed to do and let the existing converter in the trailer do what it was designed to do, i.e. provide 12 volts off shore power?


    They said there are two outlets on the RV so they would have to wire it in two places and they do not want to do that.

    I would use a battery charger

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