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diy_rook

Gentran transfer switch L14-30

diy_rook
10 years ago

Electric newbie here..I was recently given a generator and my house always had a Gentran transfer switch (Gentran 30216) that has a L14-30 inlet. My garage has a receptacle that feeds directly to the Gentran.

My problem is that the new generator (Devilbiss GB5000 with a Briggs Genpower 10.0) doesn't have a L14 out and has what I think is Nema 6-20. Am I able to come up with a cord with a 6-20 three prong on one side and a 4 prong L14 on the other end?

Thanks in advance.

Comments (27)

  • petey_racer
    10 years ago

    Sorry, but no. You CANNOT use that generator to backfeed a home.
    You have a 120V receptacle and a straight 240V receptacle, but not a 120/240V rated receptacle you need.

    Some will say jury-rig it and combine the two you have but no way in hell I would do that. It's just not worth it.

  • diy_rook
    Original Author
    10 years ago

    Ok - Even though it would be sending 240 to the Gentran transfer switch which then has 4 15 amp circuits for 120 and a 220? I thought I could backfeed that switch with the 240 alone and the Gentran switch would determine the 220 or 120? I'm not backfeeding directly to my main box.

    Thanks

  • petey_racer
    10 years ago

    It doesn't matter.
    You CANNOT get 120V from 240V without a neutral, and your 240V receptacle on the genny has NO neutral. That is the problem.

  • Ron Natalie
    10 years ago

    As pointed out, those generator will not work and there's no way to "kludge" it so it does. It's not just a connector issue, there's no center tap on the 240 output side to make the 120/240 work.

  • diy_rook
    Original Author
    10 years ago

    Thank you both for the responses. Looks like I'll have to sell this one and get a new one.

    What would be the minimum size gen to power a 6 switch transfer switch? 4 at 120 with 15amp the 2 combined for my well pump at 220.

  • bus_driver
    10 years ago

    The well pump could be a problem- depends on the HP. Mine will JUST BARELY start on a 4000/4400 generator. Almost stalls the generator.
    Buy 6500 or larger.

  • Ray1000
    10 years ago

    Don't guess at the generator output needed to operate the well pump and possibly purchase what you can't use a second time. If you do not have the specifications for the well pump motor, attempt to locate the manufacturer's name and model number of the pump motor. The manufacturer should be able to give you both the start-up and run wattage of the motor. The start-up wattage may be as much as 2 to 3 times that of the run wattage after start-up.

    If all else fails have a master electrician test the well pump/motor wattage on the circuit during start-up. It should take him 10 minutes to accurately answer your question.

  • Auger01
    10 years ago

    You could use that generator if you installed an L14-30 outlet on it . If you aren't going to use the 240v plug on the generator, remove that outlet and replace it with the L14 outlet. Pull the neutral from one of the 120v outlets.easy piesy.

  • Auger01
    10 years ago

    Double posted

    This post was edited by Auger01 on Sun, Aug 18, 13 at 23:57

  • Ron Natalie
    10 years ago

    Sorry Auger, but you're completely wrong on this. You make the unwarranted assumption that the grounded side of the 120V receptacles on this generator is the center tap of the 240V coil. This is ****NOT**** the case for this generator. There is no center tap on the 240 side to tap into.

  • Auger01
    10 years ago

    Somebody is wrong, but it is not me. Here is a wiring diagram of a GB5000. The 240 IS center tapped for the 120 volt.

  • diy_rook
    Original Author
    10 years ago

    Excellent - thanks for the info Auger01. So I ordered a L14-30 receptacle to install on this generator. Even though the genset is only 20Amp, this is ok right? So wire #3 (neutral from the left 120 side) for my L14-30r right?

    This post was edited by diy_rook on Thu, Aug 22, 13 at 10:38

  • bus_driver
    10 years ago

    "wire #3 (neutral from the left 120 side) for my L14-30r right?"
    The confusion about which wire is one of the reasons I made no suggestions earlier.
    Suppose that we post precisely our suggestions for the generator. But do we have any confidence that the hookup at the other end will be done correctly? I don't. And a wrong hookup at any point could be disastrous.
    Based on what I have seen thus far, it is best to just leave it alone.

    This post was edited by bus_driver on Thu, Aug 22, 13 at 19:07

  • diy_rook
    Original Author
    10 years ago

    Understood - definite newbie here but I plan on having help. The other end is a L14-30 inlet in my garage that was previously installed at my house which feeds into the transfer switch directly. That end is done.

  • Auger01
    10 years ago

    Connect your neutral wire to stator lead 2 - 3 or wire 6 -7 or either of the silver terminals on the 120 volt outlet. Post a picture of what you have if you are not sure. Good luck.

    The 30 amp is fine.

    Edited to clarify stator leads vs wire numbers.

    This post was edited by Auger01 on Fri, Aug 23, 13 at 5:22

  • bus_driver
    10 years ago

    Bad advice.

  • bus_driver
    10 years ago

    Lesson learned. When responding to bad advice, copy and paste the bad information into the reply in case of later editing.

  • Auger01
    10 years ago

    Maybe instead of just saying "bad advice" bussdriver, it might be more helpful to clarify what exactly was wrong with the advice and specifiy the right way to do it.

    This is a forum where people seek help with thier projects. The OP has a basic grasp of the concepts involved so I have no problem giving him a push in the right direction. If the only answer you care to give is basically "I know the right way to do it, but I am not going to tell you because you are too dumb to do it correctly", then perhaps your time might be better spent elswhere.

  • bus_driver
    10 years ago

    My advice was to not pursue that project further. But creating a potentially fatal situation demanded a response.

    This post was edited by bus_driver on Fri, Aug 23, 13 at 21:56

  • diy_rook
    Original Author
    10 years ago

    Ok so I am going to remove the 240 outlet and install the new L14-30 receptacle. black circled (L1), combine both red circled (L2), green (ground), then connect new wire as neutral and tie into #6 (orange)? Is that right?

  • Auger01
    10 years ago

    That looks correct.

    To make it look neat, you can drill a hole in some .045" -ish aluminium sheet stock from the home center to secure the L14 outlet to and then screw the aluminium to the existing cover.

  • diy_rook
    Original Author
    10 years ago

    Excellent - I will get it going soon and will post an update. Thanks again Auger01 for the help.

  • diy_rook
    Original Author
    10 years ago

    OK I did the wiring - here is what I have now. I haven't tested it as I need to do some routine maintenance to the generator first. Please let me know if you see any errors. I used wire nuts and used some 12awg blue wire I had as a pig tail to the new L14 receptacle.

  • Auger01
    10 years ago

    The connections look correct, but check it with a multimeter when it is running anyway. Those wire nuts make me nervous. They are going to have to endure alot of vibration. They might work, but they weren't really designed for this application. Here is an alternative connector:

    http://www.amazon.com/Lockitt-POSI-TWIST-Assortment-connectors-10-26/dp/B00CMC99EW

    Good luck and let us know how it works.

  • diy_rook
    Original Author
    10 years ago

    All systems go! Auger01 - thanks a lot for the assistance through the process! If I hadn't done this - as much as I wouldn't want to I would've been forced to use the frowned upon backfeed but now this will work perfectly for me and safe for everyone. I tested with the multimeter and both 120 and the 240 are reading properly. It's not the prettiest looking right now as you can see. I'm going to cut a plate like you suggested to clean it up a bit.

    It's great to be able to post an issue like this and find a solution. I scoured the internet and couldn't find much info on how to do this so hopefully this thread will help other as well.

  • lskinney
    6 years ago
    last modified: 6 years ago

    I know this post is old but I got a gen just like this...So with this setup will it operate 20 amps or 30 amps when the plate says 20 amps when installing L14 30 plug?

  • Ron Natalie
    6 years ago

    A 5KW generator can only deliver 20A at 240.