The Electrical Contractor Network

ECN Electrical Forum
Discussion Forums for Electricians, Inspectors and Related Professionals

Books, Tools and Test Equipment for Electrical and Construction Trades

Register Now!

Register Now!

We want your input!

Featured:
   

2017 NEC and Related
2017 NEC
Now Available!

   
Recent Posts
Sprinklered equipment 26-008
by bigpapa
Yesterday at 04:24 PM
On Delay Relay with Auto Reset
by Potseal
12/01/16 09:59 AM
Wow, that was close!
by jraef
11/28/16 07:06 PM
Earthquake in New Zeeland
by RODALCO
11/27/16 11:25 PM
Calling all Non-US members!! (Non-US only)
by Tjia1981
11/27/16 06:33 AM
New in the Gallery:
12.5A through 0.75mm˛ flex (just out of curiosity)
Shout Box

Top Posters (30 Days)
gfretwell 15
HotLine1 10
Trumpy 8
Texas_Ranger 8
sparkyinak 7
Who's Online
0 registered (), 97 Guests and 5 Spiders online.
Key: Admin, Global Mod, Mod
Topic Options
Rate This Topic
#201431 - 05/31/11 07:56 PM Sharing a neutral
Cinner Offline
Member

Registered: 12/01/04
Posts: 77
Loc: Kelowna, B.C., Canada
On a 3 phase panel - if 2 circuits share a neutral - do you have to use a 2 pole breaker so that if one trips they both trip?

Top
2014 / 2011 NEC & Related Books and Study Guides
#201441 - 05/31/11 10:47 PM Re: Sharing a neutral [Re: Cinner]
twh Offline
Member

Registered: 03/11/04
Posts: 898
Loc: Regina, Sask.
14-010. It depends on whether the circuit feeds lights or plugs.

It isn't a trip issue, though. We can still use fuses as long as we include a disconnect that meets the requirements of 14-010(b).

Top
#201442 - 05/31/11 10:57 PM Re: Sharing a neutral [Re: twh]
Cinner Offline
Member

Registered: 12/01/04
Posts: 77
Loc: Kelowna, B.C., Canada
It is for receptacles. Can you use 15 amp single pole breakers if the neutrals are being shared to more than one circuit?

Top
#201444 - 06/01/11 09:30 AM Re: Sharing a neutral [Re: Cinner]
jay8 Offline
Member

Registered: 07/28/05
Posts: 183
Loc: Vancouver, BC
the trade practice for three phase 4 wire circuits feeding 120/347 volts loads is single pole breakers. I could see good justification for a three pole breaker to ensure a circuit is completely disconnected included any current on a shared neutral but I dont think any code rule requires it. If the receptacle/load is using more than one phase then you need to use 2 or 3 pole breaker.

Top
#201447 - 06/01/11 01:30 PM Re: Sharing a neutral [Re: jay8]
jay8 Offline
Member

Registered: 07/28/05
Posts: 183
Loc: Vancouver, BC
and before a bunch of posts come about the implications of common breaker handle for single phase loads, I can see some change in installation practice that will reflect the issue of current on shared neutral - such separate neutrals etc

Top



ECN Electrical Forums - sponsored by Electrical Contractor Network - Electrical and Code Related Discussion for Electrical Contractors, Electricians, Inspectors, Instructors, Engineers and other related Professionals