How can I determine if magnetic starter (switch) on my Grizzly 1023 is damaged?

[Bob AZ]

Dan & Jeff

Maybe the "double breaaker" is in fact one of theose breaker bodies that has two breakers in one housing so each breaker is on he same leg!!

Bob AZ

[JJ]

Yes, he put in a L6-30 receptacle and a matching plug on the saw. I'll check the voltage across the hot legs at the receptacle when I get home tonight. I suspect it will be the same as in the switch (each hot to the ground will be 120v, but nothing across the hots). And yes, he ran new 10/2 cable from a double pole breaker to the new receptacle.

So, if each hot leg is supplying 120v, and they are coming off a double pole breaker, does it make any sense for no volts across the two hots? Could this be a bad breaker?

Jeff

[Tom Veatch]

If someone who wasn't watching or didn't know what they were doing connected the wrong wires to the breakers, you could have that condition. If the circuit is wired with NMC, you'll see the white wire from one cable going to one breaker and the black wire going to a different breaker. If you can't tell which wires feed the circuit, trip the breaker and make sure both hot wires at the saw show zero voltage to ground. If not, then one of the wires is connected to a different breaker. If that's the case, keep tripping breakers until both wires are cold. Then, swap the affected wires to correct the problem. That's assuming the wire gauges that are swapped are correct for the breaker they finally land on.

If that's not the case, it could be, as suggested elsewhere, the breaker in use is not the correct type for the distribution box. I've also heard tales of boxes in which some positions aren't usable for double pole breakers because adjacent positions don't span both legs. If that's the case, you'll see both wires go cold when you trip the breaker. To correct that, you'll need to rearrange the vertical position of the breakers so the double pole breaker is in the correct position. I don't know if such boxes exist or not. In my limited experience, I've not encountered one, or haven't noticed if I did.

One other thought is that if the circuit was "self-installed" and a half height breaker (two breakers in a single position) was used, or if someone has been monkeying around with the wiring and both wires ended up landing on one of those, you'd see the results you're seeing. I assume that's not the case since you'd surely have noticed that by now.

Tom Veatch Wichita, KS USA

[Nova]

I may not be all that bizarre if it's an old house with only a 120V service.

[Scott Lurndal]

More likely either not really a double pole breaker, or it was installed in the wrong slot in the panelbox. Some panelboxes only provide stubs for double pole breakers in certain positions.

scott

[Lew Hodgett]

All panel boxes will only allow 2P c'bkrs to be installed in true 2P locations.

That said, there was a time when certain manufacturers provided handle tie kits that could be improperly installed on a pair of 1P c'bkrs which does not provide a 240V ck't, but rather a a 120V ck't.

Lew

[Bob AZ]

Jeff

Possible code violation unless there is a dedicated ground system in use. Rarely seen.

Also there is a possibility that your juristiction may require the cable to be 10-3 with ground. This would give you a black, red and white wire in the cable along with the ground.

Bob AZ

[B A R R Y]

How do all those 240v air conditioners I see locally work with a 3 prong plug? These are brand new installations.

I seriously doubt they are all violations.

[Tom Veatch]

What do those jurisdictions require be done with the white wire which won't bet connected to anything on either end?

Tom Veatch Wichita, KS USA

[Tom Veatch]

I think the most prevalent case is to simply use the bare ground wire in the #/2 cable for the ground. Almost universally seen.

Tom Veatch Wichita, KS USA

[B A R R Y]

That's how I understand it. Two hots and a ground, no neutral.

Dryers and stoves need the neutral, because they also need 120v from the same circuit.

[Lew Hodgett]

It's a nomenclature problem.

"10/2" is shorthand for 10/2/WG.

IOW: L1(Black), L2 (Red), and bare earth ground in a common sheath.

"10/3" same as above except add N(White).

Lew

[Nova]

Very common, provided the connectors are a type 250 Volt NEMA 6-XX (where XX = the rated amperage) connector to prevent a 120V appliance from being plugged into the 220V outlet (and vise versa).

[Tom Veatch]

...

Lew, are you sure you didn't misspeak there? As I recall, all the 2+G NMC I've seen was Black/White/Bare. I've not seen the Red wire except in 3+G cables. Maybe there's a different NMC color combination cable for use in 240v circuits?

Don't think you'd want to choose a Black/Red/Bare for a 120v circuit. 'Course that's probably no worse than using Black/White/Bare for 240v.

Tom Veatch Wichita, KS USA

[Nova]

I believe you are correct Tom. The white wire has to be either wrapped with black electrical tape or marked with a permanent black marker to indicate it is used as a hot lead.

[Lew Hodgett]

I stand corrected.

Need to remember to engage brain before hitting key.

Lew

BTW, I NEVER trust color codes. Always "ring" the circuit as I go.

Lew

[David G. Nagel]

The black wire is attached to the first breaker, the red wire is connected to the second breaker, the white wire is connected to the ground strip mounted around the breakers. The other end of the cable is connected in a similar fashion. The black is attached to one blade socked, the red is connected to the other blade socket, the white is attached to the ground socket. The green wire is attached to the case at each end of the cable.

Dave N

[Bob AZ]

Barry

A 240 volt installation requires only 2 wires and ground. Two hots and a ground if you will.

I don't know of any cable of the type mentioned by the OP that are just one black and one red wire with a ground. So the closest cable available that I am familiar with that meets the NEC has a red and black and a white wire together with a ground wire.

If a two wire cable with ground is used it is usually with a black and a white wire with a ground. In this case the white wire must be ID'ed, usually with red tape. There are also requirements for how the tape is used for identification.

Take care Bob AZ

[Bob AZ]

Tom

I am not sure what the jurisdictions and/or the NEC require for the unused white wire. I see them cut back, just left hanging, taped back and just pushed out of the way. I usually tape them back or cut them back. Sometimes I find a wirenut on the white wire.

It is always nice to find a white wire to use for a neutral for a low current use. Much more than a few amps and I run another hot from another circuit breaker.

Just a note here:

220 volt appliances now require a separate neutral, white wire, if there are any 110 volt loads. Such as receptacles etc.

Bob AZ

[Bob AZ]