Electrical Advice please

[Old Coastie]

I have an air compressor with a 15-amp, 230-V motor.
I have a generator with a 220-V outlet, configured as shown in the picture.

Here is my question: The compressor motor has two wires from the motor to the switch terminal. There are two screw terminals, each marked “line” and a ground terminal.
So, from the plug, the L-shaped prong is ground. Which two of the other three prongs should go to the “line” terminals on the motor?

I have a severe aversion to things blowing up in my face. Can you help?

 

[Cleanworks]

I have an air compressor with a 15-amp, 230-V motor.
I have a generator with a 220-V outlet, configured as shown in the picture.

Here is my question: The compressor motor has two wires from the motor to the switch terminal. There are two screw terminals, each marked “line” and a ground terminal.
So, from the plug, the L-shaped prong is ground. Which two of the other three prongs should go to the “line” terminals on the motor?

I have a severe aversion to things blowing up in my face. Can you help?

View attachment 97899 View attachment 97900

You're asking us? It's the red wire, no, I mean the blue wire. Maybe the yellow wire.

 

[FB19087]

The one across from the ground is the neutral....other two hot....I think

 

[Lee Stockwell]

Get a Volt ohm meter to verify your connections. The black and red are BOTH hot, 120v to ground and neutral and 240 to each other.

 

[FB19087]

 

[Sierra Clean Care]

Electrical scares the shit out of me....
Years ago, I was visiting a friend who was doing some electrical work in his basement suite. He was crouched down in the space where the range goes, working on the 220.
It was a beautiful summer day, birds were chirping, you could hear the sound of neighbours mowing the grass....
I was sitting at the kitchen table, shooting the Shyte, drinking a beer.
I asked him if the breaker was off....
‘Of course’ was his reply...
Well....
Not 5 seconds later, I was taking a sip of my beer, and a large white flash appeared out of the corner of my eye....
Next thing I knew, he was laying at my feet, eyes rolling around like he was having a seizure....
The guy has NEVER been the same since....
I hate electrical.....

 

[Lee Stockwell]

That's why there is a lockout protocol.

We did one flood at Murray State in the IT building where there was water and backwash debris under a platform floor in the main computer room.

They SAID they cut all the power, shut down the mainframe, and were ready for us to go under and start the clean up.

I didn't trust that at all. We bought a probe to confirm, and right away Jason found a 408 v line they didn't realize was still there, and HOT.

 

[Old Coastie]

What if there is no neutral terminal on the compressor motor? Do I just hook up two hots? The two top terminals are labeled “motor” and the two below are labeled “line.” The green is ground, obviously. But there is no neutral from the motor. Does ground suffice for the neutral?

 

[sassyotto]

try it. then we will all know

 

[Cleanworks]

What if there is no neutral terminal on the compressor motor? Do I just hook up two hots? The two top terminals are labeled “motor” and the two below are labeled “line.” The green is ground, obviously. But there is no neutral from the motor. Does ground suffice for the neutral?
View attachment 97902

Sure.

 

[Old Coastie]

Okay.... Inspired by the general confusion, I looked it up. Turns out that for 220-240, one ignores the neutral line altogether. So, 10 gauge wire, make up to the generator plug on the two hots and simply let ground be ground. To the compressor, hardwire the two hots and ground, light ‘er off and see what happens.
Fred, thanks for the diagram above.

 

[clean image]

i am no means a electrician

however we run 220 stone machines and I maintain and have replace the 220v internal switch

usually only the hot wires ( 120 plus 120= 240 ) are switched, common and grounds are always connected

on our stone machine we do not use the common, as it does not have/require one. Many older houses, before they change the electric code did not have a common wire. just 2 hots and a ground- 3 plug for dryers and stove.

 

[Lee Stockwell]

There are variations and exceptions to the rule. More emphasis on safety in the later 4-wire design. Floating ground and ground fault situations along with opportunities for fire and electrocution abound.

 

[Fat Mike]

That's why there is a lockout protocol.

We did one flood at Murray State in the IT building where there was water and backwash debris under a platform floor in the main computer room.

They SAID they cut all the power, shut down the mainframe, and were ready for us to go under and start the clean up.

I didn't trust that at all. We bought a probe to confirm, and right away Jason found a 408 v line they didn't realize was still there, and HOT.

Wild leg

 

[Lee Stockwell]

What if there is no neutral terminal on the compressor motor? Do I just hook up two hots? The two top terminals are labeled “motor” and the two below are labeled “line.” The green is ground, obviously. But there is no neutral from the motor. Does ground suffice for the neutral?
View attachment 97902

Typically "ground" and neutral are electrically equivalent, however the green "ground" wire is meant to safely ground the major metal elements of a machine or appliance. The neutral wire facilitates splitting power from a 240 v apparatus to a 120 v part, like a motor, light, solenoid, or such.

 

[Fat Mike]

That’s why I call my bro n law he’s an electrician so was his dad before he passed.

Been trying to get him to get licensed and venture out on his own.

Got shocked few weeks ago when set up fence for my dog who learned how to jump our 6’ wall

 

[hogjowl]

@Jim Martin
I wouldn’t do anything until you hear from him
He’s better than the experts here

 

[Cleanworks]

Free advice is worth every penny.

 

[Lee Stockwell]

@Jim Martin
I wouldn’t do anything until you hear from him
He’s better than the experts here

Like many here who had a "real job" in the early years cleaning, I worked in plant maintenance.

 

[Fat Mike]

@hogjowl

relative of yours?

 

[Jim Martin]

230/240 motors are phased..

Line one is one phase and line 2 is the other..... Typically on most types of motors ground acts as a netural...

So any where that it says line in.. That is power.. So line in from the cord cap to line in to the motor...

Netural ( white) and green are both negative wires and act to complete the circuit....

Green is a physical ground and is used more commonly on motors...

 

[hogjowl]

Bam!
Shut up

 

[Lee Stockwell]

Bam!
Shut up

Because you finally understand?

 

[hogjowl]

Can’t you read?

 

[Willy P]

Do we have a fried Stephen or a sushi Stephen,?

 

[Mikey P]

Because you finally understand?

Not till he gets a PHX...

 

[hogjowl]

No need

 

[SamIam]

Electrical scares the shit out of me....
Years ago, I was visiting a friend who was doing some electrical work in his basement suite. He was crouched down in the space where the range goes, working on the 220.
It was a beautiful summer day, birds were chirping, you could hear the sound of neighbours mowing the grass....
I was sitting at the kitchen table, shooting the Shyte, drinking a beer.
I asked him if the breaker was off....
‘Of course’ was his reply...
Well....
Not 5 seconds later, I was taking a sip of my beer, and a large white flash appeared out of the corner of my eye....
Next thing I knew, he was laying at my feet, eyes rolling around like he was having a seizure....
The guy has NEVER been the same since....
I hate electrical.....

Shocking

 

[Hack Attack]

used to work with a guy who reckoned he'd been hit by lightning 5 times..

we called him Igor..

dunno about the 5 hits but he wasn't "right"

 

[Steve Lawrence]

Hope you got good goggles! (or a stupid neighbor.)