service equipment

roger

Moderator
Staff member
Location
Fl
Occupation
Electrician
No, see the definition of "Service Equipment" in article 100.

Roger
 

mortimer

Member
Location
newengland
No, see the definition of "Service Equipment" in article 100.

Roger
Indeed, I have, but I feel that it can be interpreted in a way that would allow a sub panel to be treated as service equipment. For example, if a meter was changed to a meter main, would you have to change a range that was wired with #6 SE cable to a 4 wire?
 

Dennis Alwon

Moderator
Staff member
Location
Chapel Hill, NC
Occupation
Electrical Contractor
Indeed, I have, but I feel that it can be interpreted in a way that would allow a sub panel to be treated as service equipment. For example, if a meter was changed to a meter main, would you have to change a range that was wired with #6 SE cable to a 4 wire?

Some areas may allow it to remain but you have made a service panel a non service panel and thus the se cable would not be compliant from a sub.

Once you have a main breaker or use the 6 handle rule then any panel after the main is not service equipment.
 

jaggedben

Senior Member
'Subpanel' is not a code term but the way myself and everyone else I know uses the term it is by definition not service equipment. In fact I would say it's primarily used to communicate that a panel is not service equipment.

I completely agree with Dennis regarding changing the role of a panel.
 

LarryFine

Master Electrician Electric Contractor Richmond VA
Location
Henrico County, VA
Occupation
Electrical Contractor
Yes, any time you add a new main disconnect upstream, everything after should be re-wired as a sub-panel would be, including major-appliance circuits, receptacles, power cords, etc.

This is triggered when, for example, a transfer switch is added to an existing service; the T/S becomes the service, and GECs and the main bond are supposed to be relocated there, etc.
 

jap

Senior Member
Yes, any time you add a new main disconnect upstream, everything after should be re-wired as a sub-panel would be, including major-appliance circuits, receptacles, power cords, etc.

This is triggered when, for example, a transfer switch is added to an existing service; the T/S becomes the service, and GECs and the main bond are supposed to be relocated there, etc.
Not exactly.

You'd only treat everything downstream as a Subpanel if the new "Main Disconnect" had overcurrent protection incorporated into it.

JAP>
 

roger

Moderator
Staff member
Location
Fl
Occupation
Electrician
Indeed, I have, but I feel that it can be interpreted in a way that would allow a sub panel to be treated as service equipment. For example, if a meter was changed to a meter main, would you have to change a range that was wired with #6 SE cable to a 4 wire?
I can't see any way it can be interpreted except it is not service equipment any more. Per the NEC yes, you would have to change it.

Some areas may allow it to remain but you have made a service panel a non service panel and thus the se cable would not be compliant from a sub.
And to expand on that, if an inspector allowed it he would not be doing his job.

Roger
 

Dennis Alwon

Moderator
Staff member
Location
Chapel Hill, NC
Occupation
Electrical Contractor
I can't see any way it can be interpreted except it is not service equipment any more. Per the NEC yes, you would have to change it.

And to expand on that, if an inspector allowed it he would not be doing his job.

Roger

NC allows it in some situations


250.140 Frames of Ranges and Clothes Dryers.Frames of electric ranges, wall-mounted ovens,counter-mounted cooking units, clothes dryers,and outlet or junction boxes that are part of thecircuit for these appliances shall be connected tothe equipment grounding conductor in the mannerspecified by 250.134 or 250.138.

Exception No. 1: For existing branch-circuitinstallations only where an equipment groundingconductor is not present in the outlet or junctionbox, the frames of electric ranges, wall-mountedovens, counter-mounted cooking units, clothesdryers, and outlet or junction boxes that are partof the circuit for these appliances shall bepermitted to be connected to the grounded circuitconductor if all the following conditions are met.
(1) The supply circuit is 120/240-volt, singlephase, 3-wire; or 208Y/120-volt derived froma 3-phase, 4-wire, wye-connected system.
(2) The grounded conductor is not smaller than10 AWG copper or 8 AWG aluminum.
(3) Any of the following:
a. The grounded conductor is insulated;
b. The grounded conductor is uninsulated andpart or a Type SE service-entrance cableand the branch circuit originates at theservice;
c. The grounded conductor is uninsulated andpart of a cable assembly and all current carrying conductors are protected by a ground-fault circuit interrupter at the origination of the branch circuit; or
d. A new 3-wire cable assembly not smallerthan the existing conductors shall bepermitted to be extended from the service toan enclosure where the existing conductorsshall be spliced together and provisions aremade so that the grounded conductors areinsulated by tape, heat-shrink or otherapproved means inside the enclosure.
(4) Grounding contacts of receptacles furnishedas part of the equipment are bonded to theequipment

Exception No. 2: For existing branch-circuitinstallations only where an equipment groundingconductor is not present in the outlet or junctionbox, an equipment grounding conductor sized inaccordance with 250.122 shall be permitted to berun separately from the circuit conductors.
 

Little Bill

Moderator
Staff member
Location
Tennessee NEC:2017
Occupation
Electrician
Sometimes it is nearly impossible to run a new cable for a range or dryer. The inspectors here look at situations like this and will allow taping of a bare neutral to prevent accidental contact with anything non-current carrying.
 

roger

Moderator
Staff member
Location
Fl
Occupation
Electrician
NC allows it in some situations
Dennis, existing installations would mean nothing else has changed. There has never been an exception to allow a three wire branch circuit where it was never allowed in the first place and it was never allowed from a "subpanel".

Roger
 

roger

Moderator
Staff member
Location
Fl
Occupation
Electrician
Dennis, existing installations would mean nothing else has changed. There has never been an exception to allow a three wire branch circuit where it was never allowed in the first place and it was never allowed from a "subpanel".

Roger
I should have pointed to Exception 1 (3)(b) of 250.140 to accompany my post.

b. The grounded conductor is uninsulated and part or a Type SE service-entrance cable and the branch circuit originates at the service;


Roger
 

Dennis Alwon

Moderator
Staff member
Location
Chapel Hill, NC
Occupation
Electrical Contractor
Roger I am pretty certain that the intent of the bold was added to accommodate the situation we are talking about. I can check with Joe but I seem to remember going over that with him
 

roger

Moderator
Staff member
Location
Fl
Occupation
Electrician
Roger I am pretty certain that the intent of the bold was added to accommodate the situation we are talking about. I can check with Joe but I seem to remember going over that with him
Dennis, I would like to hear what Joe has to say about it not being fed from the service equipment. Regardless, NC's amendments do not change the NEC which does not have any exception to the requirement that a three wire branch circuit as covered in 250.140 must originate at the "Service Equipment"

Roger
 

Dennis Alwon

Moderator
Staff member
Location
Chapel Hill, NC
Occupation
Electrical Contractor
My point was that it is allowed in some areas. Granted the NEC doesn't allow it.

Nc has gone further for an existing 3 wires run to an old service panel that is now a sub panel

Exception No. 5: It shall be permissible to groundan existing panelboard enclosure by connectionto the grounded circuit conductor for a one- andtwo-family dwelling where all the followingconditions apply:
(1) When relocating or installing an additionalmain disconnecting means;
(2) Enacting 250.142(B) Exception No. 5: (1)redefines the existing service entranceconductors as a feeder as set forth in Article100;
(3) An equipment grounding conductor in theexisting panelboard is not present;
(4) Replacement of the existing service entranceconductors either requires the removal of thebuilding finish or is deemed impractical by theauthority having jurisdiction.
(5) All grounding electrode conductors areremoved completely from the existingpanelboard; and(6) The grounded conductors are insulated bytape, heat-shrink, or other approved meansexcept where covered by the sheathing of acable assembly or as needed for joints, splices,and termination purposes.
 

roger

Moderator
Staff member
Location
Fl
Occupation
Electrician
My point was that it is allowed in some areas. Granted the NEC doesn't allow it.

Nc has gone further for an existing 3 wires run to an old service panel that is now a sub panel

Exception No. 5: It shall be permissible to groundan existing panelboard enclosure by connectionto the grounded circuit conductor for a one- andtwo-family dwelling where all the followingconditions apply:
(1) When relocating or installing an additionalmain disconnecting means;
(2) Enacting 250.142(B) Exception No. 5: (1)redefines the existing service entranceconductors as a feeder as set forth in Article100;
(3) An equipment grounding conductor in theexisting panelboard is not present;
(4) Replacement of the existing service entranceconductors either requires the removal of thebuilding finish or is deemed impractical by theauthority having jurisdiction.
(5) All grounding electrode conductors areremoved completely from the existingpanelboard; and(6) The grounded conductors are insulated bytape, heat-shrink, or other approved meansexcept where covered by the sheathing of acable assembly or as needed for joints, splices,and termination purposes.
I think they need to work on their wording.

How do you install an "additional main disconnecting means", how many "main disconnecting means" can you have? ;)

They should have worded it something like, "When relocating" the existing service location.

Roger
 

jap

Senior Member
I should have pointed to Exception 1 (3)(b) of 250.140 to accompany my post.



Roger
That's an interesting point.

Seeing as how there is no branch distribution in a Meter/Main setup (unless you purchase it with it) , isn't the existing Service Panel (although now actually a subpanel) still the first "Service Panel" where a branch circuit can be taken from ?


JAP>
 

mortimer

Member
Location
newengland
That's an interesting point.

Seeing as how there is no branch distribution in a Meter/Main setup (unless you purchase it with it) , isn't the existing Service Panel (although now actually a subpanel) still the first "Service Panel" where a branch circuit can be taken from ?


JAP>
This is getting exciteing. All kinds of interpretation :eek:hmy:
 

jap

Senior Member
You cant get a branch circuit from a standard service disconnect without any distribution.


JAP>
 
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