630.12 and 630.13

Dale001289

Senior Member
Location
Georgia
Need some feedback on this one...

Client wants to put up to six welding receptacles (480V, 3Ph, 40A each) on a single, 60A three-pole circuit breaker from a distribution panelboard located in the piperack - not far from receptacles. The arc-welders to be utilized have not been defined; and no one knows if they'll l have an integral disconnecting means or not. Plus, the welding recept's do NOT have an integral disconnecting means - they are simply daisy-chained together (in parallel of course) without any additional overcurrent protection or disconnecting means.

Are there any circumstances where this would be allowed?
 

iwire

Moderator
Staff member
Location
Massachusetts
A plug and receptacle s a disconnecting means.

As far as the OCP it depends on the welders so that is a bit of an issue.
 

Dale001289

Senior Member
Location
Georgia
A plug and receptacle s a disconnecting means.

As far as the OCP it depends on the welders so that is a bit of an issue.
This is a Crouse Hinds 480V receptacle. The plug has to be twisted into place - where it locks...hardly meets the intent of 'disconnect switch'.
Besides, would you feel comfortable removing the plug under load?

I say this violates 630.12, 630.13 and 210.21(B)(3)...in addition, they're putting 6, 40A receptacles on a single 60A branch circuit breaker...not nearly enough demand factor available under article 630; yet another violation.
 
The plug has to be twisted into place - where it locks...hardly meets the intent of 'disconnect switch'.
Why not? You can use it to disconnect/isolate the welder. How is that not the intent?

Besides, would you feel comfortable removing the plug under load?
I wouldn't, but that's not usually the purpose of a disconnect.
Disconnecting Means. A device, or group of devices, or other means by which the conductors of a circuit can be disconnected from their source of supply.
 

GoldDigger

Moderator
Staff member
This is a Crouse Hinds 480V receptacle. The plug has to be twisted into place - where it locks...hardly meets the intent of 'disconnect switch'.
Besides, would you feel comfortable removing the plug under load?

I say this violates 630.12, 630.13 and 210.21(B)(3)...in addition, they're putting 6, 40A receptacles on a single 60A branch circuit breaker...not nearly enough demand factor available under article 630; yet another violation.
If you look at the UL listing fpr NEMA standard receptacles, they are rated for load breaking. A disconnect is NOT a safety switch, so the time and effort needed to open it is not an issue.
Demand factor (and calculated load) apply based on what is plugged into the receptacles, not their rating (with the exception of general purpose receptacles in residential.)
1. These are dedicated purpose receptacles.
2. If the customer has only one welder there is no need to apply any demand (diversity) factor.
 

Dale001289

Senior Member
Location
Georgia
If you look at the UL listing fpr NEMA standard receptacles, they are rated for load breaking. A disconnect is NOT a safety switch, so the time and effort needed to open it is not an issue.
Demand factor (and calculated load) apply based on what is plugged into the receptacles, not their rating (with the exception of general purpose receptacles in residential.)
1. These are dedicated purpose receptacles.
2. If the customer has only one welder there is no need to apply any demand (diversity) factor.
Have you ever tried to disconnect one of these things? Really requires some effort. But ok, lets pretend you're right,
this is still a code violation. Arc-welders hit very high current when in full use even though they're intermittent; combine three or four 'striking' at the same time and your supply conductors could become quite warm, thus the installation doesn't conform to 210.21(B)(3) or 610.12 especially when there's one pathetic 60A CB protecting 6each @ 40 = 240A; even with demand, I'd say you need two 100A CB's at the panelboard with three welders on each.
 

iwire

Moderator
Staff member
Location
Massachusetts
Have you ever tried to disconnect one of these things? Really requires some effort. But ok, lets pretend you're right,
this is still a code violation.
We are not going to pretend he is right, he is right. A plug and receptacle is a code compliant disconnecting means.

You seem to be under the impression the NEC required disconnecting means is an emergency disconnect. It is not, it's only purpose is to allow killing power to work on the equipment. If it was a disconnect switch you could even padlock it in the on position.

Arc-welders hit very high current when in full use even though they're intermittent; combine three or four 'striking' at the same time and your supply conductors could become quite warm, thus the installation doesn't conform to 210.21(B)(3) or 610.12 especially when there's one pathetic 60A CB protecting 6each @ 40 = 240A; even with demand, I'd say you need two 100A CB's at the panelboard with three welders on each.
I will get back to this tomorrow but you really don't seem willing to learn new things.
 

GoldDigger

Moderator
Staff member
The OP specified six receptacles. He did NOT specify six welding machines. I envision one machine being moved from place to place.
If there will be six machines, then I doubt that what is proposed would be compliant.
 

Dale001289

Senior Member
Location
Georgia
The OP specified six receptacles. He did NOT specify six welding machines. I envision one machine being moved from place to place.
If there will be six machines, then I doubt that what is proposed would be compliant.
This is a large LNG plant, not a warehouse....during shutdown there will be several machines cranking at the same time. This is not code compliant.
 

Dale001289

Senior Member
Location
Georgia
We are not going to pretend he is right, he is right. A plug and receptacle is a code compliant disconnecting means.

You seem to be under the impression the NEC required disconnecting means is an emergency disconnect. It is not, it's only purpose is to allow killing power to work on the equipment. If it was a disconnect switch you could even padlock it in the on position.



I will get back to this tomorrow but you really don't seem willing to learn new things.
Don't you suppose the folks who write this stuff (NFPA, CMP's etc) understand that welding receptacles REQUIRE a plug? If the plug was meant to be THE disconnecting means for the receptacle, mentioning the word 'disconnect' in article 610.13 would be redundant and absurd - see where I'm going with this? Your rationale is flawed.
The plug is NOT intended to be the disconnect...seems you got some learnin' to do also
 

iwire

Moderator
Staff member
Location
Massachusetts
Don't you suppose the folks who write this stuff (NFPA, CMP's etc) understand that welding receptacles REQUIRE a plug? If the plug was meant to be THE disconnecting means for the receptacle, mentioning the word 'disconnect' in article 610.13 would be redundant and absurd - see where I'm going with this? Your rationale is flawed.
The plug is NOT intended to be the disconnect...seems you got some learnin' to do also
Stick around and learn something.

This is for motors

430.109 Type. The disconnecting means shall be a type specified in 430.109(A), unless otherwise permitted in 430.109(B) through (G), under the conditions specified.(F) Cord-and-Plug-Connected Motors. For a cord-and-plug-connected motor, a horsepower-rated attachment plug and receptacle having ratings no less than the motor ratings

(F) Cord-and-Plug-Connected Motors. For a cord-and-plug-connected motor, a horsepower-rated attachment plug and receptacle having ratings no less than the motor ratings
shall be permitted to serve as the disconnecting means. A horsepower-rated attachment plug and receptacle shall not be required for a cord-and-plug-connected appliance in ac-cordance with 422.33, a room air conditioner in accordance with 440.63, or a portable motor rated 1⁄3 hp or less.
Do you still think a plug can not be a disconnecting means?

I can keep posting. :huh:
 

iwire

Moderator
Staff member
Location
Massachusetts
Don't you suppose the folks who write this stuff (NFPA, CMP's etc) understand that welding receptacles REQUIRE a plug?
Welders are not required to have plugs, they can be, and often are hardwired, in those cases another form of disconnecting means is required.
 

Dale001289

Senior Member
Location
Georgia
I don't see any requirement to have the disconnect within sight or any specified distance, so the circuit breaker is your disconnect.....am I missing something, what's the issue??

Article 610.13 states EACH receptacle requires a disconnect- in normal practice disconnects are located the load side of the circuit. Also, there is no mention anywhere of plug being used as a disconnect, which infers it cannot suffice for such.

Article 210.21(B)(3) allow multiple receptacles on a circuit, unless they are used exclusively for welders, as in this case.

So to answer your question, 'Yes', actually you're missing quite a lot.
 

Little Bill

Moderator
Staff member
Location
Tennessee NEC:2017
Occupation
Electrician
99% of the time that I have wired multiple receptacles for a welder was for convenience, so they can move the machine to different locations without having to have long extension cords.

@ the OP, you need to find out if in fact they have welders for each receptacle. If they do then you need to address the OCD, if not, the breaker (60A) likely is fine.
As for the plug being a disconnect, it is!!!:happyyes:
You say "unplugging them under load", why not just turn the welder off!:thumbsup:
You likely could get to the switch as quick or quicker than getting to the plug.
As was mentioned, the disconnect is not an emergency switch or safety switch, it is to disconnect the machine from power while servicing it.
 

iwire

Moderator
Staff member
Location
Massachusetts
Article 610.13 states EACH receptacle requires a disconnect- .
I do not think it does, here it is from 2008 NEC, I don't have the 2014 handy so it may have changed.

630.13 Disconnecting Means. A disconnecting means shall be provided in the supply circuit for each arc welder that is not equipped with a disconnect mounted as an inte-gral part of the welder. The disconnecting means shall be a switch or circuit breaker, and its rating shall be not less than that necessary to accommodate overcurrent protection as specified under 630.12.


in normal practice disconnects are located the load side of the circuit. Also, there is no mention anywhere of plug being used as a disconnect, which infers it cannot suffice for such.
To continue saying a plug is not a disconnect is as true as saying the earth is flat.

I have a service call to go to, see ya later.
 
Last edited:

david

Senior Member
Location
Pennsylvania
I do not think it does, here it is from 2008 NEC, I don't have the 2014 handy so it may have changed.







To continue saying a plug is not a disconnect is as true as saying the earth is flat.

I have a service call to go to, see ya later.
From what I am reading the disconnecting means is specified to be a circuit breaker or switch for welders that do not have a switch as a disconnect.

630.13 Disconnecting Means.
A disconnecting means shall be provided in the supply circuit for each arc welder that is not equipped with a disconnect mounted as an integral part of the welder.
The disconnecting means shall be a switch or circuit breaker, and its rating shall be not less than that necessary to accommodate overcurrent protection as specified under 630.12.
NFPA 70 / 2008

Looking at 2011 it pretty much says the same thing. I guess for welders you would not consider the rec. as the required disconnecting means. although rec. certainly are normally allowed as the required disconnecting means
 
Last edited:
FWIW, for reasons stated above, I wouldn't install any sort of switch next to a welding receptacle. The OP is free to do so if they want to. Both will be code-compliant installations.

As david mentioned
The disconnecting means shall be a switch or circuit breaker...
Surely seems to me that unless you're using fuses everywhere, the OCPD is an appropriate disconnecting means.

However, one might get caught up in
630.33 Disconnecting Means. A switch or circuit breaker shall be provided by which each resistance welder and its control equipment can be disconnected from the supply circuit.
but that's a different kettle of fish.
 
Article 610.13 states EACH receptacle requires a disconnect- in normal practice disconnects are located the load side of the circuit. Also, there is no mention anywhere of plug being used as a disconnect, which infers it cannot suffice for such.

Article 210.21(B)(3) allow multiple receptacles on a circuit, unless they are used exclusively for welders, as in this case.

So to answer your question, 'Yes', actually you're missing quite a lot.
As has been noted, it doesn't say "receptacle" it says "each arc welder." For the case of one circuit feeding multiple welders or multiple welder receptacles, I am not sure I agree that the ocpd can't be the disconnect for all welders/receptacles.
 
Top