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220v wiring, right or wrong?

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wyliesdiesels

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Can't believe we got this far into this thread without someone flatly stating, "three wire is not to code1"

Answer, it depends. Some local electrical codes require four-wire for any 240-volt outlets in a garage. OTOH, my local utility wired the ESVE for my EV with a three-wire outlet and the city inspector passed it. When I questioned it, referring to all the GJ experts, I was told four-wire is only required when there is an appliance with a 120-volt leg inside it.

jack vines
this makes no sense at all. if its a 240v receptacle, there is no need or use for a neutral

please cite this local code including the AHJ that has it. remember, has to be a WRITTEN amendment to the NEC
 

wyliesdiesels

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There are 3-wire and 4-wire 240V EVSEs. Can't find a code cite on that changing the requirements for a garage though.
if its 240v then it isnt 4-wire. 4-wire would be 120v/240v.

and i dont see the point in having a 4-wire circuit for an EVSE. what does it need 120v for?
 

wyliesdiesels

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Better back up and figure out if there's an equipment ground ran with the feeder.

If you remove the jumper on a 3 wire feeder you are creating a major issue because you will have NO ground.
if you look where the feeder comes into the bottom of the panel, you can see a very small black wire. Im assuming this is the EGC. looks too small

If this is indeed the EGC, then the bars should be unbonded
 
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strength_and_power

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you wont overload the neutral in this case because its a 240v receptacle so the neutral isnt needed and further, no current flows on the ground terminal or EGC under normal operation.
Would you mind expanding on what “overloading the neutral “ means?
Thanks
 
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strength_and_power

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What gauge should the ground be? Trying to pull a single wire in a conduit won’t be fun if even possible. Can the shop have its own ground rod or two?
 

NostraThpmas

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I see a mix of GE and SquareD breakers. I didn't think SquareD made classified breakers for GE. I know he said he is replacing the panel soon, so this probably doesn't matter. Just odd.
 

sparky 1971

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What gauge should the ground be? Trying to pull a single wire in a conduit won’t be fun if even possible. Can the shop have its own ground rod or two?
It should have a #8 equipment ground back to the house panel and since it's a detached garage, it needs two ground rods. If it were pre 2008 a three wire feed with a bonded neutral would have been compliant.
 

wyliesdiesels

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What gauge should the ground be? Trying to pull a single wire in a conduit won’t be fun if even possible. Can the shop have its own ground rod or two?
detached buildings need both an EGC (which goes between house and shop panels) AND a GEC going to the rods. you cannot substitute the GEC for an EGC. they are different animals and serve different purposes

see diagram in post #3 and explanation of GEC and EGC in post #4

 

mm08822

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It should have a #8 equipment ground back to the house panel and since it's a detached garage, it needs two ground rods. If it were pre 2008 a three wire feed with a bonded neutral would have been compliant.
It also has a bare GEC run out out the lower left bottom of panel. What it's connected to is another q for the OP.
 

mm08822

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if you look where the feeder comes into the bottom of the panel, you can see a very small black wire. Im assuming this is the EGC. looks too small

If this is indeed the EGC, then the bars should be unbonded
Looks bare to me.
 

mm08822

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What gauge should the ground be? Trying to pull a single wire in a conduit won’t be fun if even possible. Can the shop have its own ground rod or two?
It probably won't be fun and could require pulling everything back out to run a #8 copper ground wire.

Is there a complete conduit run from panel to panel?
If yes, how complicated is it?
If no, then a shovel is in your future to correct it.

You are required to have 2 ground rods in a detached structure from the building that has the main panel. Sparing various details/exceptions, leave it as 2 rods.

Ground rods do not provide the same function as an equipment grounding conductor run with the feeder.
 
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dcg9381

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if its 240v then it isnt 4-wire. 4-wire would be 120v/240v.
and i dont see the point in having a 4-wire circuit for an EVSE. what does it need 120v for?
You, as usual, have the correct semantics.

My guess is because that most modern homes that have a 50A circuit have a 14-50R, so that's the common plug on 240V EVSEs.

The charger that came with our Ford has two "pig tails" on it. One is a 15A circuit @ 120V, standard plug. The other is a 14-50P. The EVSE auto-senses depending on which pig tail you put on it. After market EVSE is the same thing.. If I was buying one (EVSE), why not get one that I can take with me and easily adapt to a number of different receptacles?
 
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dcg9381

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Best reason I've heard is RV parks use 14-50R's.
I think it's more about modern residential using this as the "dryer" receptacle in many garages.

Yea, the RV parks haven't figured out that they are "free" fueling stations for PHEVs or EVs towing RVs.
 

mm08822

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I think it's more about modern residential using this as the "dryer" receptacle in many garages.

Yea, the RV parks haven't figured out that they are "free" fueling stations for PHEVs or EVs towing RVs.
Around here, dryer recepts are in the house and would be 14-30s.
 

dogdog

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If I was the op, I would just kept the L14-30 setup and just make a pigtail to convert the L14-30 to 6-something for 240 stuff. That is what I did. Otherwise already mentioned, just cap that neutral and put a label on it both at the panel and at the box.
 

mm08822

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You have it right... I've installed so many 14-50s, I forgot that the dryer is different.
What are all of the garage 14-50's you mention used for prior to EVSE needs? Not too prevelent around here.

EVSE owners are really the first to require them and that's b/c of them needing to adopt to the common practice of EVSE industry.

Anything else in a garage requiring higher power levels were comps and welders only using 6-30 or 6-50's.
 

dcg9381

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What are all of the garage 14-50's you mention used for prior to EVSE needs? Not too prevelent around here.
Someone corrected me. 14-30s are more common. I just use 14-50s as they are my 240V standard across the board and I forgot there was a difference on the plug.
EVSE owners are really the first to require them and that's b/c of them needing to adopt to the common practice of EVSE industry.
Anything else in a garage requiring higher power levels were comps and welders only using 6-30 or 6-50's.
You have it right. That's the 14-50 is the receptacle being added to more modern homes that are "EV equipped" not 14-30 that's used for electric dryers.
 

wyliesdiesels

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Someone corrected me. 14-30s are more common. I just use 14-50s as they are my 240V standard across the board and I forgot there was a difference on the plug.

You have it right. That's the 14-50 is the receptacle being added to more modern homes that are "EV equipped" not 14-30 that's used for electric dryers.
but if you only need 240v, its the wrong receptacle. (FYI plug goes on the end of a cord, not in the wall). for 50a 240v you would use a 6-50R
 

dcg9381

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but if you only need 240v, its the wrong receptacle. (FYI plug goes on the end of a cord, not in the wall). for 50a 240v you would use a 6-50R
Right, but if you want a multi-function receptacle, it's the right one to get (speaking pragmatically). RVs need the neutral and many EVSE's have this plug. I totally get that a 6-50R is the right deal for "240 only".

for what? only equipment in a house that uses a 14-50 is a range
RVs, EVSEs (most come with this plug as default). I run my welder on that circuit. I use it as our charge plug for charging Lithium Iron Phosphate batteries via 13kW inverters.

Oh yea, these guys had it as a standard connection for charging their boats at my shop:

1719263580225.png
 
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strength_and_power

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detached buildings need both an EGC (which goes between house and shop panels) AND a GEC going to the rods. you cannot substitute the GEC for an EGC. they are different animals and serve different purposes

see diagram in post #3 and explanation of GEC and EGC in post #4

Thanks for the link, I read it and will be reading it again for sure
 
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strength_and_power

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It probably won't be fun and could require pulling everything back out to run a #8 copper ground wire.

Is there a complete conduit run from panel to panel?
If yes, how complicated is it?
If no, then a shovel is in your future to correct it.

You are required to have 2 ground rods in a detached structure from the building that has the main panel. Sparing various details/exceptions, leave it as 2 rods.

Ground rods do not provide the same function as an equipment grounding conductor run with the feeder.
I believe there is a conduit from the shop to the house, from where the house panel is and where the electrical enters the shop is a pretty straight shot, I have no problem digging if need be.

I will look outside the shop for a ground rod or two, would they typically be at the edge where the slab meets the ground or a distance away?
 

sparky 1971

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I believe there is a conduit from the shop to the house, from where the house panel is and where the electrical enters the shop is a pretty straight shot, I have no problem digging if need be.
If it's conduit all the way, the best bet is going to be to pull everything out and pull it back in with a green #8. But, before I did that, I would try attaching the same green #8 to the little ground wire that is already there and try pulling it out with the new wire in. It probably won't work, but I'm lazy enough that I would have to try.
I will look outside the shop for a ground rod or two, would they typically be at the edge where the slab meets the ground or a distance away?
Follow that bare conductor leaving the panel on the bottom left. It should lead you to a ground rod, I doubt there are two, but if it happens to be the case, there should be a conductor connecting them and should be at least 6' apart.
 
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