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Sir Sparks
Sir Sparks, President/Owner/ Master Electrician
Category: Electrical
Satisfied Customers: 2532
Experience:  US State Certified & UK Electrical Contractor for all electrical fields/disciplines
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I am wiring a contactor to a well pump with a float switch.

Resolved Question:

I am wiring a contactor to a well pump with a float switch. The contactor has a 120 volt coil. The pump is 240 volt. The wire to/from the pump float is 18 gauge.
Submitted: 7 years ago.
Category: Electrical
Expert:  Sir Sparks replied 7 years ago.

-Could you explain your situation a little more?


What is your question?

Edited by Sir Sparks on 3/26/2010 at 11:41 PM EST
Customer: replied 7 years ago.
Can you give me a diagram on how to wire this contactor?
The contactor is 120 volt but the supply and the load are 240 volt.
There is also the 18 g wire from the well float. Should I install an in-line fuse on the 18g
to prevent overload ?
Expert:  Sir Sparks replied 7 years ago.

Hi, I don't do diagrams but it is so easy anyway.


240 volt feed; one wire to each side of contacts on contactor then 1 wire from each other side to pump.


Also one side of feed wires to one side of contactor with second side to float switch, finally the last wire of float switch to neutral.


No need for an inline fuse.

Customer: replied 7 years ago.
Don't I need to bypass one leg of the 240 feed since the contactor coil is 120 volt, not 240?
To make it more clear:
One leg each of 240 to L1 and L2.
A jumper from one of those legs to contacts with the other contact wired to the float switch. Second wire from float switch is wired to a neatral ground.
Then T1 and T2 to well pump.
Expert:  Sir Sparks replied 7 years ago.
Yes, to neutral. But not ground. That is what I said; one leg to contactor coil, other leg of coil to float, second wire of float to neutral.
Customer: replied 7 years ago.
I am confused.
My 240 is single phase, 2 lines and a ground.
What is the neutral line?
Expert:  Sir Sparks replied 7 years ago.
I see. You MUST use a neutral or change the coil to 240 volts. No choice, sorry.
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