Magnetic Switch for Air Compressor - Question

tuna_fan

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Has anyone here installed a magnetic switch on their air compressor? I bought a WEG switch, and I have some questions about the wiring of it...specifically which (if any) jumper wires I need to remove, and where to put the two wires from my pressure switch onto the WEG switch. I can post pics if anyone thinks they can help out...thanks!
 

xbskt

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Has anyone here installed a magnetic switch on their air compressor? I bought a WEG switch, and I have some questions about the wiring of it...specifically which (if any) jumper wires I need to remove, and where to put the two wires from my pressure switch onto the WEG switch. I can post pics if anyone thinks they can help out...thanks!
Post a picture of a terminal or wiring diagram or a link to it.
Model number might help also.
 

tuna_fan

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Post a picture of a terminal or wiring diagram or a link to it.
Model number might help also.
Thanks!
Here is the info:



WEG 5 HP Single Phase Magnetic Starter Electric Motor Control NEMA 1 208-240 V



WEG ESWS-25V24E-RM34 5 HP Single Phase Magnetic Starter

Photos of actual switch attached, along with diagram from inside cover:


I see where to put my power into the switch, and to the motor. My main questions are relating to the pressure switch control wires from my compressor, that I would like to use to control your mag switch. I have 2 wires (plus ground) that I would like to connect to your switch… 2 questions:
  1. Do I need to remove any of the current jumper wires that are installed on the mag switch currently (from factory).
  2. Where should I run the 2 pressure switch wires into ? (I suspect one wire goes to “1L1” and one goes into “A1”)

weg2.jpg

weg1.jpg

weg8.jpg

weg7.jpg

weg5.png

weg4.jpg
 

xbskt

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Remove wire C that goes from 3-L2 to 96
I don't see wire D in the pictures. It may not be supplied from the factory. It may be the jumper to 13 to the auxiliary contacts you would use to power something else when the compressor is running. (remote on light, cooling fan, run time clock, whatever) You can leave the jumper to 13 if you want.
The two wires from the pressure switch go 96 and A1.
A1 and A2 are the coil for the contactor. A2 gets power from 95. A1 needs the other leg of 110 to power the coil from 96. This happens by taking power from 96 through the pressure switch and back to A1.
To confirm operation prior to completion briefly touch the new wire ends together. Contactor should pull in when touched and open when separated. If you have the compressor motor and mag switch wired but not the pressure switch just put the wires (or just a pair of temporary one foot piece on the terminals as I say and touch them together briefly by swiping them past each other.
All this is doing is running the power for the contactor coil through the pressure switch. If you don't remove the jumper you would need a "stop" button or 3 wire control.

Long story short remove jumper C and the two wires from the pressure switch go to 96 and A1

Of course I just wire houses for a living so is my best guess and this advice is worth what you paid.
 

tuna_fan

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Remove wire C that goes from 3-L2 to 96
I don't see wire D in the pictures. It may not be supplied from the factory. It may be the jumper to 13 to the auxiliary contacts you would use to power something else when the compressor is running. (remote on light, cooling fan, run time clock, whatever) You can leave the jumper to 13 if you want.
The two wires from the pressure switch go 96 and A1.
A1 and A2 are the coil for the contactor. A2 gets power from 95. A1 needs the other leg of 110 to power the coil from 96. This happens by taking power from 96 through the pressure switch and back to A1.
To confirm operation prior to completion briefly touch the new wire ends together. Contactor should pull in when touched and open when separated. If you have the compressor motor and mag switch wired but not the pressure switch just put the wires (or just a pair of temporary one foot piece on the terminals as I say and touch them together briefly by swiping them past each other.
All this is doing is running the power for the contactor coil through the pressure switch. If you don't remove the jumper you would need a "stop" button or 3 wire control.

Long story short remove jumper C and the two wires from the pressure switch go to 96 and A1

Of course I just wire houses for a living so is my best guess and this advice is worth what you paid.
Thanks Jeff! I will give this a shot tonight....thank you!
 
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