Air Comressor wiring question

[arvidj]

... that is, using two phases (hot lines), then the switch must be double pole.

I think it is split-phase ... single phase with neutral grounded ... not two phase, and you are correct, it will require a double pole switch.

 

[Fabrickator]

I just have mine wired to it's own dedicated breaker. I use a number of my breakers as switches for lighting and service disconnects.

Technically, you're not supposed to use a breaker for a disconnect except for lighting if its rated to do so (HD). I've done the same thing with my compressor for years until I finally hard wired it to a 20a circuit with wall switch.

 

[Eddyde]

I think it is split-phase ... single phase with neutral grounded ... not two phase, and you are correct, it will require a double pole switch.

You are correct in that common 200+ volt service isn't officially called "two phase", it is called "single phase" but it does in fact use two phases and no neutral. One phase and a neutral is also commonly called "single phase" or "split phase" yielding typical 115-125 volt service. Then of course there is "three phase" which uses all 3 phases....All of which is a common source of confusion for many trying to understand AC electricity.

 

[John Hasler]

You are correct in that common 200+ volt service isn't officially called "two phase", it is called "single phase" but it does in fact use two phases and no neutral. One phase and a neutral is also commonly called "single phase" or "split phase" yielding typical 115-125 volt service. Then of course there is "three phase" which uses all 3 phases....All of which is a common source of confusion for many trying to understand AC electricity.

Electricians often refer to the two hot lines ("L1" and "L2") of a single-phase 240VAC center tap grounded service as phases. They're wrong (but there's no point in trying to tell them so). A two phase service would have two pairs of wires with their voltages 90 degrees out of phase.

 

[Wreck™Wreck]

I just picked up a really nice Porter Cable 60 gal compressor for the shop/garage. In the owners manual it states that there should be an on/off switch between the main power and the pressure switch. I've never heard of or seen this before. It's a 3.7 HP 240v single phase 17.2 FLA.


Anyone heard of this? What should I use for the switch? It actually says it will void the warranty by not having one.


Thanks all.[/

Code, local disconnect within sight of the device, does not require lockout/tagout protocol for maintenance.

 

[f350ca]

Technically, you're not supposed to use a breaker for a disconnect except for lighting if its rated to do so (HD). I've done the same thing with my compressor for years until I finally hard wired it to a 20a circuit with wall switch.

That was my thought too, but the electrical inspector said it was ok (again with the right type of breaker) if the device was in sight of the panel. Been going to add a push button operated relay between my phase converter and the panel but the project went way down the list when he said it was ok the way I had it.

Greg

 

[Eddyde]

Electricians often refer to the two hot lines ("L1" and "L2") of a single-phase 240VAC center tap grounded service as phases. They're wrong (but there's no point in trying to tell them so). A two phase service would have two pairs of wires with their voltages 90 degrees out of phase.

I never called it "two phase" I simply noted that it uses 2 "phases" and no neutral, which is correct. A "Phase" being an alternating wave of electrical energy. In this case they are 180 degrees apart. I know they are split at the transformer from one single phase but what most people are dealing with to make 2xx volt power are essentially "two phases".

The 90 degree "true two phase", 4 wire system you describe is long obsolete.

 

[gunrunnerx]

Thank you all for your insight and advice.

Dman1114, that is the one! I got it for $351. :rubbinghands:
I love it. Can't wait to finish getting the sub panel wired up and then deal with this.

Ill look around for a disconnect box and see what I can find fairly reasonably and try to get it up and going. I did pick up a "dryer" whip and socket but am having second thoughts.

 

[umahunter]

Heres like what I have

 

[umahunter]

Can take pics if ya need them