1. Welcome to Tundras.com!

    You are currently viewing as a guest! To get full-access, you need to register for a FREE account.

    As a registered member, you’ll be able to:
    • Participate in all Tundra discussion topics
    • Transfer over your build thread from a different forum to this one
    • Communicate privately with other Tundra owners from around the world
    • Post your own photos in our Members Gallery
    • Access all special features of the site

Alternator to power RV

Discussion in 'Towing & Hauling' started by Bigolbaddy, Aug 6, 2020.

  1. Aug 6, 2020 at 5:18 PM
    #1
    Bigolbaddy

    Bigolbaddy [OP] New Member

    Joined:
    Oct 3, 2019
    Member:
    #36961
    Messages:
    214
    Gender:
    Male
    First Name:
    Ben
    Fort Worth
    Vehicle:
    2020 MGM 1794
    So I heard from a trusted source that a HD alternator, like one from a ambulance, could be used to replace the oem. Has anyone done this and run the heavy wire to the pin and replaced the receiver with a 9 pin to power their trailer with 120?
     
  2. Aug 6, 2020 at 6:16 PM
    #2
    ezdog

    ezdog New Member

    Joined:
    Mar 1, 2020
    Member:
    #43363
    Messages:
    2,719
    Gender:
    Male
    Gateway To The West
    Vehicle:
    2001 RCLB V8,4WD 2015 RCLB 5.7,4WD
    Your connection to the trailer from the truck is really just to charge the trailers battery/s while the truck is on the road.

    Are you not getting enough or fast enough charging now or is there some other reason that you think you will gain something by doing this?

    Do you have one battery on the truck or two? I guess a higher output alternator might provide faster charging for the multiple truck batteries and the trailer batteries but is there really some reason you think you need this?
     
  3. Aug 6, 2020 at 6:18 PM
    #3
    Bigolbaddy

    Bigolbaddy [OP] New Member

    Joined:
    Oct 3, 2019
    Member:
    #36961
    Messages:
    214
    Gender:
    Male
    First Name:
    Ben
    Fort Worth
    Vehicle:
    2020 MGM 1794
    Current system works as it should. What I am asking is if anyone has upgraded their alternator to an Heavy duty and then run a 9 pin so 120 is available from the truck?
     
  4. Aug 6, 2020 at 6:26 PM
    #4
    ezdog

    ezdog New Member

    Joined:
    Mar 1, 2020
    Member:
    #43363
    Messages:
    2,719
    Gender:
    Male
    Gateway To The West
    Vehicle:
    2001 RCLB V8,4WD 2015 RCLB 5.7,4WD
    120 what exactly?

    Do you mean 120 vac power?
     
  5. Aug 6, 2020 at 6:34 PM
    #5
    Festerw

    Festerw New Member

    Joined:
    May 7, 2017
    Member:
    #7600
    Messages:
    3,693
    Gender:
    Male
    Cambridge Springs, PA
    Vehicle:
    04 Tundra DC
    I don't believe the systems on those put out 120 from the alternator but use an inverter to power their accessories.
     
    NewImprovedRon and AZBoatHauler like this.
  6. Aug 6, 2020 at 8:18 PM
    #6
    19TurdPro

    19TurdPro New Member

    Joined:
    Jul 27, 2019
    Member:
    #33771
    Messages:
    897
    Gender:
    Male
    Vehicle:
    2019 Tundra TRD Pro
    Alternators are DC. An ambulance gets its power from batteries and an inverter, and uses a high output alternator to top off the batteries.

    I understand mods can be done to convert it to AC power, but I can't see a practical use for powering 120vac from the truck to the trailer. It might be able to put out enough amperage to power a TV and a few other things, but not enough for the AC unit at an idle, if at all. The noise and the CO2 emissions of the running truck would be much greater than a Honda generator.
     
    Festerw and AZBoatHauler like this.
  7. Aug 7, 2020 at 5:43 AM
    #7
    ezdog

    ezdog New Member

    Joined:
    Mar 1, 2020
    Member:
    #43363
    Messages:
    2,719
    Gender:
    Male
    Gateway To The West
    Vehicle:
    2001 RCLB V8,4WD 2015 RCLB 5.7,4WD
    Actually Alternators natively generate AC( Alternating Current) power which is why they use a Diode Bridge to chop that into the DC that we all use for the vehicle and battery charging.
    Further they rely on the battery to filter the choppy DC into smoother DC current that the vehicle can make use of in the end.

    The deal is that there is a whole lot of difference between 12v and 120v if that is even what the OP is talking about?
    I still can not be sure?

    There are a lot of reasons to not run AC power to a trailer to power its loads though and Ambulances and other commercial vehicles that rely on 120vac power do indeed run either an Inverter to create it from the Battery Power on board and/or run a Generator for the making of the 120vac.

    I have owned a few Ambulances too and currently have a TV Broadcast Van and all of these had both a Genset and Commercial Inverter for this on board.
     
  8. Aug 7, 2020 at 5:45 AM
    #8
    Rex Kramer

    Rex Kramer Vinyl Spinner

    Joined:
    Apr 9, 2017
    Member:
    #7181
    Messages:
    6,620
    Gender:
    Male
    Georgia
    Vehicle:
    2002 4.7L RCLB 4X4 2007 5.7L RCSB 4X2
  9. Oct 28, 2020 at 2:49 AM
    #9
    hundytundy

    hundytundy New Member

    Joined:
    Aug 26, 2020
    Member:
    #51391
    Messages:
    26
    I (think) I kind of get what the OP was asking. I'm currently looking to swap in a 270A alternator, which can then charge my aux battery, which powers a 3000W Inverter. The inverter will send 120VAC down an extension cord to the trailer's inverter (kind of like plugging in to shore power), which then charges the trailer's 800aH Lithium battery pack. So, does anybody see a downside to this method?
     
    Bigolbaddy[OP] likes this.
  10. Oct 28, 2020 at 3:24 AM
    #10
    Festerw

    Festerw New Member

    Joined:
    May 7, 2017
    Member:
    #7600
    Messages:
    3,693
    Gender:
    Male
    Cambridge Springs, PA
    Vehicle:
    04 Tundra DC
    Nothing besides wasted energy on the conversation assuming that the trailer batteries are 12v also.

    Why not just send a heavier gauge 12v wire from the aux battery to the trailer?
     
  11. Oct 28, 2020 at 4:00 AM
    #11
    hundytundy

    hundytundy New Member

    Joined:
    Aug 26, 2020
    Member:
    #51391
    Messages:
    26
    Going 12V over 50ft (after all the twists and turns) would require a DC-DC charger, limiting you to 40 or 50 amps, and require a 3/0 or 4/0 AWG welding cable (costing the same as an inverter). Going 120VAC can provide 100+ amps to the trailer...
     
  12. Oct 28, 2020 at 5:46 AM
    #12
    Danman34

    Danman34 New Member

    Joined:
    Sep 19, 2018
    Member:
    #19579
    Messages:
    2,231
    Gender:
    Male
    First Name:
    Danny
    Vehicle:
    2018 White Tundra TRD Sport
    Considering everything in your 2020 truck is regulated and ran through the ecu, even your alternator, simply swapping to a high output alternator is far more trouble than it’s worth. You should already have a 170 amp alt as is. It’s probably a much better, feasible, and cheaper option to simply get a small portable generator to put in the back of the truck.
     
  13. Oct 28, 2020 at 6:28 AM
    #13
    Festerw

    Festerw New Member

    Joined:
    May 7, 2017
    Member:
    #7600
    Messages:
    3,693
    Gender:
    Male
    Cambridge Springs, PA
    Vehicle:
    04 Tundra DC
    That doesn't really matter though as you still have to convert that 120v back to 12v and the battery charger is only going to output what it is capable of which is probably at most 50a DC. So around 10 amps AC.

    You're going to convert 12v to 120v then back to 12v and probably lose 30% of the energy to do it, maybe 20% if the converter/inverter are efficient. Where you'll only lose about 1% over 50 feet with 4 gauge wire, no charger is necessary since you're directly connecting 12v to 12v.

    If you're set on 120v consider what @Danman34 suggested and get an inverter genset.
     
  14. Oct 28, 2020 at 7:03 AM
    #14
    Randy Morton

    Randy Morton Life takes its toll, please have exact change.

    Joined:
    May 15, 2016
    Member:
    #3378
    Messages:
    1,582
    Gender:
    Male
    First Name:
    Randy
    Deepinahearta, Texas
    Vehicle:
    2012 Tundra Double Cab, Beta Variant (I call it my Land Yacht)
  15. Oct 28, 2020 at 7:10 AM
    #15
    hundytundy

    hundytundy New Member

    Joined:
    Aug 26, 2020
    Member:
    #51391
    Messages:
    26
  16. Oct 28, 2020 at 7:40 AM
    #16
    Bigolbaddy

    Bigolbaddy [OP] New Member

    Joined:
    Oct 3, 2019
    Member:
    #36961
    Messages:
    214
    Gender:
    Male
    First Name:
    Ben
    Fort Worth
    Vehicle:
    2020 MGM 1794
    This was definitely my ask, but written much better. The reason behind it has to do with 100% dry camp and wanting that AC ability without the generator (I have a Generac that runs at 95+ decibels). Issues behind that. Truck isn’t as loud, truck is always with the trailer, generator might not be... generator is worse on fuel than the Tundra.

    I wanted to use the truck as a shore connection like hundytundy suggested.
     
  17. Oct 28, 2020 at 8:18 AM
    #17
    Festerw

    Festerw New Member

    Joined:
    May 7, 2017
    Member:
    #7600
    Messages:
    3,693
    Gender:
    Male
    Cambridge Springs, PA
    Vehicle:
    04 Tundra DC
    You're never getting 100amp 120v to it using an inverter from a 12v battery, you'd need a 12000 watt inverter using 1100 12vDC amps.

    Even using a 3000w inverter you're looking at maybe an hour run time without running the truck. If you have to have the truck running to keep it going are you really ahead considering the wear on a constantly idling truck engine?

    Get something like one of these and call it a day.

    https://www.homedepot.com/p/CHAMPIO...ickid=wlLRVbxoPxyLRzJwUx0Mo38KUkEx-gyumTOVyM0

    https://www.homedepot.com/p/Generac...erRUSH-Technology-50-State-CSA-7129/304982270
     
  18. Oct 28, 2020 at 7:04 PM
    #18
    hundytundy

    hundytundy New Member

    Joined:
    Aug 26, 2020
    Member:
    #51391
    Messages:
    26
    I'm looking for the best solution that allows my truck to charge my trailer while driving. Secondarily, in cases where solar is not being productive (or is having issues), I need a way to provide a quick top up of the house batteries.

    Previously I mentioned 100amp, but I meant 10amp (50ft extension cord) @ 120VAC.

    So, in this case we're looking at 1200 watts of power from truck inverter to trailer inverter/ charger.
     
  19. Oct 29, 2020 at 5:02 AM
    #19
    Festerw

    Festerw New Member

    Joined:
    May 7, 2017
    Member:
    #7600
    Messages:
    3,693
    Gender:
    Male
    Cambridge Springs, PA
    Vehicle:
    04 Tundra DC
    If that's the case then your truck is already equipped (if you have the factory towing package) with a 12v (30a if I remember correctly) charging line at the 7 pin harness that's meant for exactly for charging the trailer battery.

    There's also the safety factor to consider with running a hot 120v cord to a moving trailer while moving.
     
  20. Oct 29, 2020 at 5:12 AM
    #20
    hundytundy

    hundytundy New Member

    Joined:
    Aug 26, 2020
    Member:
    #51391
    Messages:
    26
    Ya, you can get a trickle charge over that 7pin connector... But that’s it.

    Definitely, precautions need to be taken with that hot 120V cord.
     

Products Discussed in

To Top