Wiring to air comp pressure switch

[jproaster]

So I'm finally getting around to finishing my air comp system.
The Quincy qtv 54e has a Condor pressure switch which is not illustrated in the instructions; instructions include another Condor with different retaining screws 6 screws vs my 5.

So it appears that I should crimp my incoming 8 gauge stranded copper to the same type connectors as the line out to motor. But I'm not sure where my ground goes. There appears another screw with a the letter "J" molded into the plastic. Hopefully the pic will show this.

I can do simple electrical...like wiring my shop last year. But I think it's wise to ask you all for input.

Thanks
John

 

[Citation]

Your ground goes to the screw into the base of the switch. The important bit is the ground wire should connect to the metal part of the pressure switch housing. There is another green wire already attached to that screw, presumably from the motor. It also needs to be attached.

 

[matt_i]

It looks like in the background there's a green wire landed on the case of the metal backplane for the switch. IMO you should have a ground at the motor case itself, and that wire should run back thru the conduit or SO-style cord to the pressure switch enclosure. You can wire-nut the big grounds together (sometimes easier than trying to get several ring terminals together on the same screw in a small space) but there should also be a smaller ground wire to bond the switch enclosure, I'd use #12 and there are premade ground wires at most home centers but finding the THHN-stranded wire versions is trickier. Last time I checked Menards carried them but the blue and orange stores didnt.

 

[jproaster]

Thanks gents.
I'll get the proper attaching parts from the electric supply ... ensure good contacts given the vibratory issues.

John

 

[jproaster]

The drama continues...
I used 8 stranded copper wire with a 40 amp breaker- as I was advised to do.
That's ok. But the fork style terminal connectors (attach in pressure switch) I need crimped to the incoming wire do not come any bigger than 10awg in my searches.
5hp btw

Suggestions?

John

 

[NitroShark]

You will need lugs. Not fork style terminal connectors. An electrical supply house will have what you need.

This is how I used lugs to wire my compressor.

 

[jproaster]

^^^So, remove the screws completely and the lugs will slide into slots?
When I tried to insert a ring terminal (to make sure I needed a fork), it wouldn't insert.
Maybe taking screw out all the way might allow a lug.

Try this tomorrow.
John

 

[Citation]

The switch should be used with the fork type connector, not the ring. The screws aren't meant to be removed. You might have to shave down the lugs to fit.

 

[jproaster]

Just bought the ring connectors for 8 awg. Gonna snip to fit.

THanks guys.

 

[jproaster]

Modified to fit. Metal still feels solid.