220v outlet sub panel... non-hot, neutral or ground?

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Old 04-29-19, 09:13 PM
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220v outlet sub panel... non-hot, neutral or ground?

I'm installing a new level 2 EV charger at our home, and just wanted to make sure I'm doing this correctly before turning the sub panel back on.

We have a 200 amp main panel on the house, with a sub panel on the back of the garage that runs off of a 70 amp breaker on the main panel. There's currently no room for a new two pole breaker on the main panel, and I already had a 220v outlet on a 40 amp breaker for my welder in the garage, running off of the sub panel. This was all done professionally, but I want to try and save a bit of money and do the EV charger myself.

Since the EV charger requires the same 40 amp breaker, I decided to hardwire the EV charger by splicing it into the welder's circuit. I've upgraded the whole run to 6 gauge wiring since it's about 70 feet from the sub panel to the charger, and also added a second 220v outlet closer to the front of the garage so I can move the welder around a bit more. They will NEVER be used at the same time. We're only going to charge the car during off peak hours at night, and I'm not much of a night welder. Main panel > sub panel > 220 outlet > 220 outlet > EV charger.

I've tried to look up but can't find the exact answer. The QUESTION... The 220 outlets are NEMA 6-50 (hot-hot-ground) and the electrician installed it using hot-hot-neutral, with the outlet's ground terminal connected to neutral on the sub panel, rather than ground. I've got everything wired up and ready to go, but before I connect that last wire and turn it all back on, I wanted to understand why it previously went to neutral instead of ground, and if it needs to still go to neutral.

Attached is an image of the sub panel if it helps. The other two-pole breaker is for a hot tub, but we're getting rid of it. Bottom left is the new 40 amp circuit with the 6 gauge wiring and the non-connected green, waiting for the proper home.

Any guidance would be greatly appreciated.
 
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Old 04-29-19, 09:30 PM
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Welcome to the forums.

We have 120v/240v electric service. No more 220

the electrician installed it using hot-hot-neutral, with the outlet's ground terminal connected to neutral on the sub panel, rather than ground.
Wrong. The green wire goes to ground..... not neutral.

No comment on the two receptacles on the same circuit.
 
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Old 04-29-19, 09:59 PM
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Thanks! No more 220... got it.

Was there any danger in the way he set it up previously, with the outlet's ground terminal connected to neutral? I've been using it for a few years this way and would love to call up and ask why they did it, if it's incorrect/dangerous.

Are you saying the two receptacles on the same circuit is not allowed? I will never be using both at the same time, as I don't have any tools other than the welder that use it. If it's somehow dangerous though, please let me know and I'll redo the setup.

If that's the case, is it also unsafe to have the EV charger on the same circuit as the welder, provided that it will never be used together? Only my wife and I live in our house, so the chances of anyone else trying to use both at the same time would be zero. However, I want to do things in a non-burning the house down manner.

Thanks again.
 
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Old 04-29-19, 10:06 PM
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I wouldn't call two 240v receptacles on the same circuit dangerous.... just not typical.
I'd make sure only the intended device is plugged in by itself.
 
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Old 04-29-19, 10:25 PM
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Ok thanks. I was just hoping you could shed some light on the other question about ground to neutral, if you don't mind.

Was there any danger in the way he set it up previously, with the outlet's ground terminal connected to neutral? I've been using it for a few years this way and would love to call up and ask why they did it, if it's incorrect/dangerous.
 
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Old 04-29-19, 10:32 PM
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It was probably an oversight on his part. The ground is only for safety in case of a direct internal short. You would still have been protected as the neutral and ground are combined at the main panel. Had the neutral opened.... that could have placed a dangerous voltage on the case of the welder.
 
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Old 04-30-19, 04:46 AM
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It is not unusual for a 240 volt circuit to have more than one receptacle for a reason you gave, so the welder could be wheeled around to different parts of the workshop or even outside.

But good wiring practice has a device such as a car charger that normally draws more than half of the amperes rating of the circuit and is hard wired, being on its own branch circuit, not having any other outlets on the circuit.

On the other hand, it is normal and common for the sum of the breaker ratings for the branch circuits originating from a panel to exceed the panel top breaker or panel feeding breaker rating.

Technically you needed a load analysis (one set of rules is at the back of the NEC book) to do the project with the hard wired car charger although you could have gotten away without the load analysis if the car charger had a cord with plug and there was a pre-existing branch circuit of appropriate amperage.
 

Last edited by AllanJ; 04-30-19 at 05:09 AM.
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Old 04-30-19, 06:39 AM
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International Residential Building Code (IRBC) limits multiple 240V outlets to 20 amps. 30A and greater should be one outlet per circuit.
 
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Old 04-30-19, 09:25 PM
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Thanks for all of the feedback. I decided to take another stab at cleaning everything up today and took some of the advice given here.

I ended up putting the EV charger and welder on their own dedicated circuits. Decided also not to go with more than one outlet for the welder, as I can just pick up a welder extension cord if I ever need to get it beyond its current range.

I decided to upgrade the rest of the garage outlets to 12 ga wiring since the previous owner was using 14 ga on a 20 amp circuit, which I had not even noticed until opening up one of the junction boxes today.

Flipped everything back on and it seems to be all good. Garage is not on fire!
 
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Old 05-02-19, 10:25 AM
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I decided to upgrade the rest of the garage outlets to 12 ga wiring since the previous owner was using 14 ga on a 20 amp circuit, which I had not even noticed until opening up one of the junction boxes today.

It appears that you have a Siemens subpanel so while you are cleaning up and upgrading, I'd suggest you replace the GE circuit breaker in the subpanel with a Siemens breaker.
 
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