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Hank F.
Hank F., Technician
Category: Small Engine
Satisfied Customers: 14733
Experience:  Certified on Onan and Generac generators
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wiring a120/240volt 4wire plug from a generator to a air compressor

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wiring a120/240volt 4wire plug from a generator to a air compressor pressure switch with 3 wire connection

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 6 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

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 6 years ago.
the pressure switch has two line connection & two load connection & one ground connect

Is the compressor 120V or 240V?

 

Customer: replied 6 years ago.
240 volts

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 6 years ago.
i am sorry the motor can be wired for 120 or 240 volts

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 6 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

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. and 2 other Small Engine Specialists are ready to help you
Customer: replied 6 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

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

I am waiting to hear from them.