How JustAnswer Works:

  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.

Ask Hank F. Your Own Question

Hank F.
Hank F., Technician
Category: Small Engine
Satisfied Customers: 13267
Experience:  Certified on Onan and Generac generators
Type Your Small Engine Question Here...
Hank F. is online now
A new question is answered every 9 seconds

wiring a120/240volt 4wire plug from a generator to a air compressor

Customer Question

wiring a120/240volt 4wire plug from a generator to a air compressor pressure switch with 3 wire connection
Submitted: 4 years ago.
Category: Small Engine
Expert:  Hank F. replied 4 years ago.

Hello,

What exactly are you wanting to know? How to actually make the connection?

 

If so, what is the voltage and amperage of the air compressor?

What is the brand and model number of the genset?

 

 

Customer: replied 4 years ago.
the generators 115/230 outlet has 4 slots which i believe is 2 hot poles a common pole and a ground pole.do i need to connect both hots to get the 230 if so thats fine the pressure switch has 2 line connections and 2 load conections if i have to use both hot leads from generator how do i wire both hots to switch,do i put them together..the wire i have has white black green red i believe green is ground white is common and black and red would be hot on the switch i'm thinking i'ld have to take black and red to 1 load connector the white to the other and the green to a grounding screw then the wires to the motor would be black from motor goes to the black and red connection on switch and white goes to the white connection on switch i hope i explained what wires and poles i have and what i'm trying to do so you can understand it if i'm right please tell me if i'm wrong please tell me how it would be wired thank you
Expert:  Hank F. replied 4 years ago.

On the 4 poles of the genset, you are correct. 2 poles are hot (black and red), one is neutral (white) and the other is ground (green).

 

You do need both hots to get 230, but they can not be connected together. The 2 line connectors on the switch is where they go.

If your compressor only has 3 wires, you will not use the ground wire. You will only have 2 hots and a neutral.

 

What is the brand and model number of the compressor, so I can try to find a schematic? Is there a schematic on the switch cover?

 

Is there any chance you could get a picture of the compressor switch box and post it here?

 

Customer: replied 4 years ago.
the pressure switch has two line connection & two load connection & one ground connect
Expert:  Hank F. replied 4 years ago.

Is the compressor 120V or 240V?

 

Customer: replied 4 years ago.
240 volts
Expert:  Hank F. replied 4 years ago.

What is the brand and model number of the compressor, so I can try to find a schematic? Is there a schematic on the switch cover?

 

Is there any chance you could get a picture of the compressor switch box and post it here?

 

Customer: replied 4 years ago.
i am sorry the motor can be wired for 120 or 240 volts
Expert:  Hank F. replied 4 years ago.

Changing the voltage on the motor requires moving several wires in the motor itself.

I will be unable to help without the schematic or instructions, so we can determine which voltage it is currently wired for.

 

I will opt out of this question so another expert may help you.

 

Customer: replied 4 years ago.
i know how to wire the motor i wanted to know what wires go to the switch.from what you are saying the black & red wires go switch white wire go to ground the ground wire is not used
Expert:  Hank F. replied 4 years ago.

From what you are describing, yes, that is the way it should be wired.

But I have never seen a neutral go to ground before. I have to wonder whether there is a wire missing. The schematic would show this.

Unless what you are calling a ground screw is actually a neutral lug. If so, this lug will be insulated from ground.

 

Hank F., Technician
Category: Small Engine
Satisfied Customers: 13267
Experience: Certified on Onan and Generac generators
Hank F. and 5 other Small Engine Specialists are ready to help you
Customer: replied 4 years ago.
can you show me a wire dirgram for the plug and how it would hook up to a pressure switch thepressure switch is a campbell hausfeld gr004500aj
Expert:  Hank F. replied 4 years ago.

I do not have this particular schematic, and have a call in to CH.

I am waiting to hear from them.

 

JustAnswer in the News:

 
 
 
Ask-a-doc Web sites: If you've got a quick question, you can try to get an answer from sites that say they have various specialists on hand to give quick answers... Justanswer.com.
JustAnswer.com...has seen a spike since October in legal questions from readers about layoffs, unemployment and severance.
Web sites like justanswer.com/legal
...leave nothing to chance.
Traffic on JustAnswer rose 14 percent...and had nearly 400,000 page views in 30 days...inquiries related to stress, high blood pressure, drinking and heart pain jumped 33 percent.
Tory Johnson, GMA Workplace Contributor, discusses work-from-home jobs, such as JustAnswer in which verified Experts answer people’s questions.
I will tell you that...the things you have to go through to be an Expert are quite rigorous.
 
 
 

What Customers are Saying:

 
 
 
  • You did one super job of explaining to me everything there is to know about this fridge. I'm looking forward to asking you questions in the future. Jimmy Bagley, IA
< Last | Next >
  • You did one super job of explaining to me everything there is to know about this fridge. I'm looking forward to asking you questions in the future. Jimmy Bagley, IA
  • Wonderful service, prompt, efficient, and accurate. Couldn't have asked for more. I cannot thank you enough for your help. Mary C. Freshfield, Liverpool, UK
  • This expert is wonderful. They truly know what they are talking about, and they actually care about you. They really helped put my nerves at ease. Thank you so much!!!! Alex Los Angeles, CA
  • Thank you for all your help. It is nice to know that this service is here for people like myself, who need answers fast and are not sure who to consult. GP Hesperia, CA
  • I couldn't be more satisfied! This is the site I will always come to when I need a second opinion. Justin Kernersville, NC
  • Just let me say that this encounter has been entirely professional and most helpful. I liked that I could ask additional questions and get answered in a very short turn around. Esther Woodstock, NY
  • Thank you so much for taking your time and knowledge to support my concerns. Not only did you answer my questions, you even took it a step further with replying with more pertinent information I needed to know. Robin Elkton, Maryland
 
 
 

Meet The Experts:

 
 
 
  • Curtis B.

    Technician

    Satisfied Customers:

    6989
    have worked on and around most engine models for 35 yrs./Polaris ATV expert
< Last | Next >
  • http://ww2.justanswer.com/uploads/KO/koboma/2012-6-6_20917_DSCF1022.64x64.JPG Curtis B.'s Avatar

    Curtis B.

    Technician

    Satisfied Customers:

    6989
    have worked on and around most engine models for 35 yrs./Polaris ATV expert
  • http://ww2.justanswer.com/uploads/SM/SmEngPro/2012-8-5_3564_Rick1206290005Edit.fullres.logo.scrn.64x64.jpg Rick's Avatar

    Rick

    Factory Authorized Trainer

    Satisfied Customers:

    4126
    Outdoor Power Equipment technical trainer since 1990, covering eight states.
  • http://ww2.justanswer.com/uploads/GI/giftindex/2011-11-19_2715_JamesLWells500.64x64.jpg James W's Avatar

    James W

    Small Engine Troubleshooting Expert

    Satisfied Customers:

    2978
    7 years as Mechanic & Parts Manager for Brother who has Owned Lawn & Garden Repair shop for 35 years
  • http://ww2.justanswer.com/uploads/jonrk/2010-1-5_22551_jon.jpg Jon K.'s Avatar

    Jon K.

    Small Engine Diagnostic Expert

    Satisfied Customers:

    2950
    Gold certified Stihl tech, Service Manager for a rental/repair shop.Certified in most small engines
  • http://ww2.justanswer.com/uploads/MR/mr2cycle/2011-3-12_03458_sears.64x64.jpg Vince O.'s Avatar

    Vince O.

    Small Engine Technician

    Satisfied Customers:

    2374
    Over 30 years experience repairing lawn and garden equipment. Chainsaws, mowers,blowers and trimmers
  • http://ww2.justanswer.com/uploads/rheisnger/2010-12-31_010856_41385_100001225699183_7012_q.jpg RUSS's Avatar

    RUSS

    SERVICE TECHNICIAN

    Satisfied Customers:

    1723
    28 YEAR SERVICE TECHNICIAN
  • http://ww2.justanswer.com/uploads/BriggsEngines/2010-02-26_230200_n1834842973_4823.jpg CJBennett's Avatar

    CJBennett

    Small Engine Technician

    Satisfied Customers:

    623
    Briggs and Stratton Master Service Tech, Kohler, Tecumseh, Kawasaki certified. 18 years exp.