Guidance for wiring pressure switch

by michael ramphal
(florida)

for husky m#h27508uwk year manf 2004







Bill says...

Hey Michael. Many pressure switches have the schematic for that switch stencilled under the lid. I take it yours doesn't?

Can anyone help Michael out with guidance on how to wire his pressure switch?

Thanks,

Bill

Comments for Guidance for wiring pressure switch

Click here to add your own comments

Sep 09, 2016
Black is Ground?
by: Anonymous

Wouldn't black and white be the power wires and green the grounding wire?

Oct 13, 2010
pressure switch wiring instructions
by: SGT KILLDIE

first of all i'm quite sure there are SOME kind of schematics on a sticker or molded into the plastic, but if not, do this....pull the cover off of the switch(if i have to tell you to unplug it first, then you've got more problems than i can solve) The switch will most likely have 2 bars which move up and down when you hit the on/off switch. Locate these and wire the white from the wall to the moving contact and the white from the motor to the fixed contact. do the same on the other side w/the green wires. and obviously the black will be your ground which is most likely going to be mounted to a nearby screw, which should have a small symbol on or near it that looks like one of those 70's era tv roof antennas. I'm not an expert, but this is pretty basic stuff...Hope this helps.

________________________

In all cases, if you are not a licensed electrician, know that you risk your life playing with electricity. If you aren't sure, don't do it.

Bill


Click here to add your own comments

Add your own question or comment. It's easy to do. How? Simply click here to return to Compressor Pressure Switch Problem.

Wiring hook up questions.


How do the electrical wires hook up on the pressure switch?

On the electrical hookups on the switch it reads line on one side and motor on the other.

The name brand of the switch is furnas electric co.






Bill answers...

Hello, and thank you very much for writing in.

If you take a look at some of the questions and answers on this page, you'll find photos of an open pressure switch that shows how it's wired.

I've uploaded a drawing of a typical Furnas pressure switch.

The line wires are the supply, the motor terminals are the wires for the motor.

If you aren't comfortable with what these mean, I don't think you should be attempting your own re-wiring.

That's why I always recommend that folks that aren't comfortable with wiring theory take a digital photo of their wiring before they start to disconnect components, to help in the re-wiring process.

Cheers,

Bill

Click here to post comments

Add your own question or comment. It's easy to do. How? Simply click here to return to Compressor Pressure Switch Problem.

Pressure switch comes apart

hi my name is steve i have a ingersol rand t20 compressor i took the pressure switch off and didnt realize that it was under load and it came apart and dont know how it goes together again

____________________
Bill says...

Darn! That can't be much fun. Glad you weren't hurt when it came apart. It's imperative that all air is dumped from a compressor before working on any part of it. But I guess you know that now, huh? :-)

There are no manuals for reassembling a pressure switch that I know of. Though they aren't terribly complex devices, there are lots of little pieces, and if they don't go back together properly, the switch won't work properly, and that's not good either.

Go to your compressor store and have a look at the pressure switches on the compressors there. Maybe even buy one, and use it as a template for putting yours back together. Then, if you cannot do it, you have a new spare to install as a replacement.

Good luck,

Bill

Click here to post comments

Add your own question or comment. It's easy to do. How? Simply click here to return to Compressor Pressure Switch Problem.

Pressure switch question

What does the little air hole do in the side of the pressure switch line ?

It has a little plunger activated by the movement on the switch?






Bill doesn't answer...

Hi Len:

Wish I could tell you for sure. Why don't you take a photo and upload it so I could see?

I suspect what you may mean is the mechanism for the unloader valve.

When the pressure in the tank reaches the set point, the pressure switch trips off, which stops the electric motor and, in turn, opens the air chamber over the piston to atmosphere, which "unloads" it through that little hole.

When the pressure in the tank reaches the "kick in" pressure point, the pressure switch turns on the electricity to the motor, and in so doing, trips that small opening closed again, so that the piston can send the air down into the tank instead of bleeding it to atmosphere through that small hole.

Cheers,

Bill

Click here to post comments

Add your own question or comment. It's easy to do. How? Simply click here to return to Compressor Pressure Switch Problem.

How to put a pressure switch back together?

by Cebert
(West Hanlin WV, United States)


21 gallon central pneumatic vertical air compressor

___________________
Bill says...

Cebert, good question. Not all pressure switches are the same in operation, or parts, and I haven't the foggiest idea in what order you took yours apart (or why, for that matter) so I can't help you reassemble it.

It's open for discussion boys and girls. Anyone help Cebert???

Thanks,

Bill

Comments for How to put a pressure switch back together?

Click here to add your own comments

Nov 28, 2015
Pressure switch bonehead
by: Bill

Ah Smitty, you are not alone my friend. It's a really aw s**t moment when the pressure switch flies apart. :-)

Nov 28, 2015
possible
by: smitty

If the Chinese can put it together we certainly ought to be able to put it BACK together. Haha. Doing the same thing with mine right now, simply because I can sometimes be a bonehead.

Dec 31, 2011
same problem - pressure switch will not go back together
by: Jason in Woodstock, Ga

I have the same problem. My Sunny E211960 pressure switch will not go back together. My Senco PC0967 is a good compressor (4.8 cfm) but I took the switch off to seal the rubber diaphragm below it. The springs and lack of a retaining area for the main metal piece that sets on the rubber diaphragm make it impossible to put back together. It main metal piece pops out the bottom every time due to the load of the springs. There has to be a way I just have not figured it out yet!!!

Click here to add your own comments

Add your own question or comment. It's easy to do. How? Simply click here to return to Compressor Pressure Switch Problem.

do you have a wiring diagram for pressure switch hook up ?

by John
(Truro Nova Scotia Canada)

we have a speedaire model 3z419j stage 1 the switch is a cw208102av 1 phase 120v 24amps Catalog No. 69lm2 series c.

Do you have a wiring diagram on how it is wired. Id you do can you please email it to us at col.sprinkler@ns.aliantzinc.ca






Bill says...

Hey John... no, I don't have a wiring diagram for your switch.

However, have you pulled off the cover and looked under the lid? Many pressure switches have the wiring diagram for their switch stencilled underneath the lid.

Failing that, have you contacted Speedaire? Follow the link from the home page nav bar to get guidelines on finding your local source.

Cheers,

Bill


Click here to post comments

Add your own question or comment. It's easy to do. How? Simply click here to return to Compressor Pressure Switch Problem.