criss
Member
- Location
- new york city
I have a 3 phase 200 amp 3/0 thhn service coming from meter can in EMT to apt 4 floors up is it necessary to run a seperate ground green wire #6 to panel ????
service grounding question
- Thread starter criss
- Start date
- Status
- Location
- Illinois
- Occupation
- retired electrician
Where is the service disconnect located?
- Location
- Chapel Hill, NC
- Occupation
- Retired Electrical Contractor
My guess is no since you are using emt. The emt can be used as your ground. Art. 358.60
Pierre C Belarge
Senior Member
- Location
- Westchester County, New York
Criss
Is this a set of service conductors or a set of feeder conductors?
Is there a disconnecting means ahead of the apt 4 floors up?
How many circuit conductors are installed inside of the EMT?
criss
Member
- Location
- new york city
grounding
grounding
the service disconnect is before the meter im tapping off a set of existing fused safety switchs in buiding basement im using 2"emt 4-3/o wires emt straight thru to apt a co worker told me i had to run a ground wire and i said not true if i was converting to greenfield then i would run a ground wire but im doing emt all the way to apt panel 3 phase
grounding
the service disconnect is before the meter im tapping off a set of existing fused safety switchs in buiding basement im using 2"emt 4-3/o wires emt straight thru to apt a co worker told me i had to run a ground wire and i said not true if i was converting to greenfield then i would run a ground wire but im doing emt all the way to apt panel 3 phase
In regard to your original post, as Dennis notes, Art 250.118 recognizes EMT as an equipment grounding conductor, and the addition of a actual conductor
is optional.
As a second point..when you say "tapping off fused safety switches" are you referencing the load side of the switch and what is the fuse size ?
(in other words, what is protecting your 3/0s)
is optional.
As a second point..when you say "tapping off fused safety switches" are you referencing the load side of the switch and what is the fuse size ?
(in other words, what is protecting your 3/0s)
criss
Member
- Location
- new york city
yes on load side of fuse and i will be using 200 amp fuses
I know we sometimes get bogged down by semantics, but this is a good example of a situation where using the proper termination makes it very clear. The NEC defines "Service" as "the conductors and equipment for delivering electric energy from the serving utility to the wiring system of the premises served". Since you are not a utility, you are not running "service" to the apartment. Your question then becomes much simpler: "I am running a feeder from the service disconnect to an apartment on the fourth floor of a building. Can the EMT conduit serve as the grounding conductor for this feeder, or do I need to install a separate grounding conductor?" 250.118 provides a list of acceptable grounding conductors. You will see that EMT is on the list, so it may be used as the grounding conductor for this feeder.
Words are important...
Words are important...
criss
Member
- Location
- new york city
thank you very much
Pierre C Belarge
Senior Member
- Location
- Westchester County, New York
criss
If you are working off a set of prints, be careful. The prints may specify an EGC for the feeder you are supplying to the 4th floor.
If you are working off a set of prints, be careful. The prints may specify an EGC for the feeder you are supplying to the 4th floor.
erickench
Senior Member
- Location
- Brooklyn, NY
The only time that I would consider using EMT as an EGC is when you are installing a pull box and the ground wire is not bonded to the box.
- Location
- Bremerton, Washington
- Occupation
- Master Electrician
Thank you. I always empasize Art 100 and using the correct terms.
The definitions are important and thats why they are listed first. Know the definition allows us to know which rules to use.
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