220v vs 240v outlet questions

[Lucien Nunes]

If it's a 10-30 dryer outlet then no, it doesn't have a ground contact. Historically it was an example of TN-C with the casing of the appliance was referenced to the neutral. But we don't know for certain what outlet the OP has.

 

[shlbydaytona89]

Well the OP appeared to me to be asking if he needed to ground the box, or the box and the reptacle (he said the receptacle has only 3 pins 2 hots and 1 neutral)

Your answer of just ground the box appeared to suggest that the receptacle does not need a ground.

Well to be clear, the 3rd wire is not a neutral (if i typed that before im sorry) but a ground, since 240 v doesn't need a neutral.

So I should ground the actual receptacle to the inside metal box? Yes or no?
Also i have a 4th wire in there doing nothing. Would just running that from the ground bar in the panel box to another ground screw inside the outlet box be added ground saftey???? Thanks

 

[shlbydaytona89]

If it's a 10-30 dryer outlet then no, it doesn't have a ground contact. Historically it was an example of TN-C with the casing of the appliance was referenced to the neutral. But we don't know for certain what outlet the OP has.

Maybe these pics will help..probably not though

 

[Lucien Nunes]

They do, and I guessed right, it's a 10-30 outlet which has two hots and a neutral but no ground. You say a 240-volt appliance does not need a neutral, but many appliances that took most of their power at 240V still had some 120V components, e.g. the timer in a 240V dryer, which ran between one hot and neutral. Obviously your lift requires only 240 but presumably does need a ground.

Today I believe an L6-30 or at least a 6-30 would be specced, as this has the two hots and ground but no neutral. I don't know the NEC well enough to say what would need to be done to change it to meet code

 

[Megawatt]

They do, and I guessed right, it's a 10-30 outlet which has two hots and a neutral but no ground. You say a 240-volt appliance does not need a neutral, but many appliances that took most of their power at 240V still had some 120V components, e.g. the timer in a 240V dryer, which ran between one hot and neutral. Obviously your lift requires only 240 but presumably does need a ground.

Today I believe an L6-30 or at least a 6-30 would be specced, as this has the two hots and ground but no neutral. I don't know the NEC well enough to say what would need to be done to change it to meet code

@Lucien for years we always used the ground actually for the neutral on a 3 wire configuration. As of the 2014 edition of the NEC if you do any work and bring it up to code which means 2 hots 1 neutral and 1 equipment ground which also means changing the cord and receptacle to a 4 wire system

 

[Lucien Nunes]

Ah OK, I was hoping you would clue me in with that. So in theory, you might find a 10-30 or 10-50 outlet with what is technically a ground, and another with what is technically a neutral? Would it be acceptable for the OP to use the L-shape prong on his 10-30 as the frame ground for his vehicle lift?

 

[Megawatt]

Ah OK, I was hoping you would clue me in with that. So in theory, you might find a 10-30 or 10-50 outlet with what is technically a ground, and another with what is technically a neutral? Would it be acceptable for the OP to use the L-shape prong on his 10-30 as the frame ground for his vehicle lift?

Yes the L shaped prong is designed for your equipment ground only but years ago it has been used as the neutral
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Yes the L shaped prong is designed for your equipment ground only but years ago it has been used as the neutral

Yes the L shaped prong is designed for your equipment ground only but years ago it has been used as the neutral

Dryers and stoves are the most widely used appliances that still to this day are using the equipment ground or L shaped prong as a neutral but as I stated if you ever have to work on them you have to bring it up to code according to the 2020 edition of the NEC to a 4 wire plug and receptacle