2008 code art 210.4 B

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scauri

Member
Never had this problem till" NOw.In n.j.only!210.4 B states:each multiwire branch circuitshall be simultaneusly disconnected with all other corrisponding breakers!?please read it and let me know how you interprete it.Am, having a very hard time with it.Up to now,in 40 years of knowlrdge,I have always put single breakers ,# different phases and aneutral feeding 3 different 120v circuits:lights and or recepticals.Only exeption{exibit 210.1 and 210.2},wich i can agree with.Had installed a 277 for lighting only as well as 2 thre phases panels feeding lights and recepticals,besides 3 phase motors.According to a n.j.inspector ,I had to replace single pole breakesTo double or triple breakers because i was using three ,or two hot legs with a neutral.Or install breaker ties!Absurd!As far back as i can remember we always installed 12-2 romex feeing two circuits in kitche ,three phase with a neutral etc.I bet you 100 % of all building work has been done that way in the past.Do you know how much money is involved if we now have to change this practic?Single neutral for each circuit ,or breaker ties?It is not practical and not right!What cvan we do to change this?Please get back.The last job almost put me out of business because of this!
 

augie47

Moderator
Staff member
Location
Tennessee
Occupation
State Electrical Inspector (Retired)
You seem to grasp the concept. If you elect to use multi-wire branch circuits (be sure to see the Code definition), then you need to meet the requirements of 210.4(B) which, at a minimum, requires the use of handle ties on SP breakers employed with MWBC.
The CMP wisdom may be questioned, but it is considered a "safety item" and hopefully the cost of the breaker tie handles was not the reason the last job almost put you out.
Not so much due to cost, but more due to the inconvenience of having multiple breakers open in the event of a short, many E/Cs here are going back to individual neutrals.
 

scauri

Member
240.4b

240.4b

thanks for your answer.Problem is that this rule is not enforced every where.I tell you i have done many jobs,still do,ion different jurisdictions where it is not applied this way.I still se many high rise buildings in nyc and other places done the same way,with no ties on breakers?Are we breaking the rules?I certainty would not want ties on my panels since i would be shutting off more than than one circuit when i don't need it.How about if there were computers or emergency equipment on the other circuits?I have worked in hospitals for 30 years.We had all multiwirte circuits with one neutral.All breakers were appropriately marked so we would always shut off the needed circuit.
Just immagine if i hads breaker ties or 3 phase brteakers feeding those multiwire circuits;iwould have to shut off all of them,causing a a big problem by cutting off power to unwanted circuits.You don't do that in hospitals.This rule stinks.It shoul d not be this way.Also remember there is a rule somewhere that you must pigtail the neutral at all times in cases like this.That prevents safety issues doesn't it? You inpectors shoul take this up with the board,have it changed.And why some authorities go for it ,some don't!?
 

scauri

Member
277 v

277 v

Also,I have not been able to get handle ties for a 277 breaker panel.Had to buy double and triple pole brks,for lots of money.
 

cowboyjwc

Moderator
Staff member
Location
Simi Valley, CA
This is why it's very important to attend code classes. Most inspectors start learning the "new" code the same time the one they're on comes out. Here we are just now adopting the 2008 code so, I've known about the two-pole breakers since about 2005.

Shouldn't have been a surprise.
 

charlie b

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Staff member
Location
Lockport, IL
Occupation
Retired Electrical Engineer
I certainty would not want ties on my panels since I would be shutting off more than one circuit when I don't need it.
There are circumstances in which a worker could be shocked, if you open one breaker associated with a MWBC, and do not open the other two. Getting shocked can be avoided if you are aware of the nature of the danger and make sure you avoid the specific circumstances that create the danger. But not everyone understands what those circumstances are, and not everyone would take the exact precautions needed to avoid the shock. Reducing the probability that someone could get shocked is deemed more important that the inconvenience of losing power to additional loads when you only need to work on one circuit.
How about if there were computers or emergency equipment on the other circuits?
If the owner has a concern that this might become an important issue, then the owner should pay the additional up-front costs of running separate neutrals. On every project I have designed over the last few years, the owner has specifically required that there be no MWBCs.
 

roger

Moderator
Staff member
Location
Fl
Occupation
Retired Electrician
thanks for your answer.Problem is that this rule is not enforced every where.I tell you i have done many jobs,still do,ion different jurisdictions where it is not applied this way.I still se many high rise buildings in nyc and other places done the same way,with no ties on breakers?Are we breaking the rules?I certainty would not want ties on my panels since i would be shutting off more than than one circuit when i don't need it.How about if there were computers or emergency equipment on the other circuits?I have worked in hospitals for 30 years.We had all multiwirte circuits with one neutral.All breakers were appropriately marked so we would always shut off the needed circuit.
Just immagine if i hads breaker ties or 3 phase brteakers feeding those multiwire circuits;iwould have to shut off all of them,causing a a big problem by cutting off power to unwanted circuits.You don't do that in hospitals.This rule stinks.It shoul d not be this way.Also remember there is a rule somewhere that you must pigtail the neutral at all times in cases like this.That prevents safety issues doesn't it? You inpectors shoul take this up with the board,have it changed.And why some authorities go for it ,some don't!?

First of all, and don't take this wrong, let me start by suggesting you locate the space bar on your key board, your posts are hard to read.

Now, my almost 40 year carreer has been mostly in hospitals and there is no argument for a hospital that can't be argued for other facilities, the fact is, inconvenience is not an argument.

I agree that the rule is not needed and geared toward the unqualified but, it is the rule

One of the ROP's for this change was due to the death of a long time electrician that was electrocuted while working on a MWBC .

Most inspectors will not have a concern with this so it is proibably up to you to submitt a proposal for changing the rule, you can find the proposal form in the back of your code book.

Roger
 

RICK NAPIER

Senior Member
Location
New Jersey
Since this was in NJ there is added confusion. New work and additions would use 2008 NEC. Repairs, reconstruction,renovations and alterations use the 2005 NEC code from chapter 6 of the Uniform Construction Code. This may explain some of the differences you have come across.
 
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