Wiring Question

[stevem99]

Long time reader, first time poster.

Background:
Air compressor is 5HP, 240v, 22amp utilizing a mag starter. Push button switch is wired in series with pressure switch. See attached diagram.

Question:
I have a 125v panel lamp I would like to add. I would like the lamp to be on whenever the push button is in the on position. If I wire it in series with the push button and pressure switch, the lamp will go off when the pressure switch shuts off the compressor. I want the lamp to be on regardless of the state of the pressure switch and for it to only go off when the push button is in the off position.

Any guidance in how I need to wire the lamp would be appreciated.

Thanks,
Steve

 

[pattenp]

The indicator lamp would need to be wired between the 120V line out side of the push switch and the neutral on the line in side of the mag starter. I assume the push button is not a momentary switch.

Also is that neutral actually a ground? The markings indicate its a ground. If you don't have an insulated white wire feeding the unit besides the L1 and L2 feeds then you don't have a neutral for the lamp to work.

 

[71flh]

So you need a light to tell you that when you're pressing the button, you're pressing the button?
Are you sure you want to have to press and keep pressing the button whenever you want the compressor to run?

I would answer no to both questions, and I'd use a toggle switch. This lets the pressure switch control the compressor when you want, and you to turn the compressor off when you want.

2nd the ground/neutral statement above.

The lamp would be wired to connect to the vertical line on the left in the pic to neutral.

 

[1grnlwn]

I am assuming that your push button switch is a toggle type switch and you want to have a pilot light to remind you to turn off the compressor at the end of the day. If the starters line side is 120 V. and uses a insulated neutral, you would attach one side of the lamp between the switch and the pressure switch and one to the neut. My compressor is hooked directly to a breaker and is never de-energized. As long as there are no leaks this works quite well. A leak free system should always be the goal, because that is where the waste occurs.

 

[bsaint]

So I was going to post this as a seperate question. For me to wire up a 240v load with household 240v, I hook 115 to the L1 and the other 115 to the N and the actual N to the ground?

 

[pattenp]

So I was going to post this as a seperate question. For me to wire up a 240v load with household 240v, I hook 115 to the L1 and the other 115 to the N and the actual N to the ground?

Whoa.. no. One 115V leg goes to L1 the second 115V leg goes to L2 and neutral goes to N and ground goes to ground. What is the 230V device/load that you are wiring for? Things such as stoves and dryers have neutrals. Welders and compressors don't have neutrals.

 

[bsaint]

Ok I didn't think that made sense but I don't know how it works with house hold wiring. At work when I need to have someone drop me a line for my equipment they give me 240 on a leg not from two legs.

Im wiring up a dual phase input (single or three) VFD. It has L1, L2, and L3 for three phase input, the same terminals are marked L1(L) L2 L3(N).

 

[bsaint]

Actually now that I think about it, Ive never dealt with single phase 240. In fact Im just using it as a supply. After that its getting converter to 24vdc for the rest of my project.

Nevermind I just figured it all out.

 

[stevem99]

I am assuming that your push button switch is a toggle type switch and you want to have a pilot light to remind you to turn off the compressor at the end of the day. If the starters line side is 120 V. and uses a insulated neutral, you would attach one side of the lamp between the switch and the pressure switch and one to the neut. My compressor is hooked directly to a breaker and is never de-energized. As long as there are no leaks this works quite well. A leak free system should always be the goal, because that is where the waste occurs.

I wired it according to pattenp's suggestion and it works great.

Correct. It is not a momentary switch. It is a plunger on/off switch and the light is simply a reminder to turn it off when done. Mine is leak free, but I don't use it everyday. I work with a guy that used to leave his energized all the time. He came home from work one evening to find the compressor running. His also was leak free until it blew a head gasket while he was gone. All valid opinions. I just prefer a simple switch and light as a precaution..

Thanks for all the good input.

Steve