Multiwire branch circuits

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don_resqcapt19

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retired electrician
I think we have here exactly the situation they have in the code making panels.

We have very knowledgeable, well meaning people that have little if, any hands on experience with a particular method deciding that they know better than the people that actually work with it based on 'what ifs'.
There should be 3 or 4 members on each CMP that have worked with the "tools". IEC, NECA, IBEW and IAEI each have reps on most if not all of the code making panels.

This rule was pushed by the IBEW safety people.
 

cowboyjwc

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Simi Valley, CA
I'm under the 2008 code. So a full 42-pole panel will all MWBC should ideally look like this:

View attachment 6996

But in reality, I just see this:

View attachment 6997

Well it's not a retrofit rule, you don't have to go back and add handle ties. We get it on all new circuit installations and on panel change out's.

Now it will change how you work on things especially if you're old school, you can't just look at a breaker now and know that it's a 3 phase or a 220v circuit.
 

roger

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Really? I was with you up to this point. Who answered this question that way? I think people here are usually pretty good at answering questions with real world answers. I think, for example, of the answers to Horsegoer about his estimating ofr wall mount fixtures as a good example.
See post # 20. It pays to read posts more than once some times.

And as an aside, protecting stupid and idiots is not a concern of mine, see the definition of "Qualified Person"

Roger
 

John120/240

Senior Member
Location
Olathe, Kansas
Is it possible to remove the handle tie temporarily to deenergize only one circuit and make repairs to the "downstream" circuit and then reinstall the handle tie?

IMO, the rule was made to protect people from doing hot work that was likely not allowed to start with.

The fact is it puts us in a position to work hot when we would not have had to without the handle ties.

Here is an ugly but very common arraignment of a MWBC in my area, you could exchange the receptacles with lights, either way is common.


MWBC1001.jpg


There is no danger in working on the one leg of this circuit after the split.

If it is possible to remove the handle tie you would only want to work on one leg after the J box

in Iwire's post 12. Then I can see the handle tie getting lost when work is done.

Its a Catch 22 If you remove the handle tie aren't we back to pre handle tie methods ??:?:?
 

hurk27

Senior Member
See post # 20. It pays to read posts more than once some times.

And as an aside, protecting stupid and idiots is not a concern of mine, see the definition of "Qualified Person"

Roger

Roger Guess the CMP's don't know "You can't fix Stupid!"
And "Stupid should hurt"

two of my favorite sayings

Also the "if you idiot proof somthing they will just create a better idiot" <<< or should that be a dumber idiot:lol:
 
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ActionDave

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Durango, CO, 10 h 20 min without traffic from wing
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There is a lot of folks here that are corrupted. MWBC are dangerous, scary, and down right evil. I'll bet if you got a look at the electrical plans for hell every circuit in there is a MWBC.

Actually, I don't believe a bit of what I said above. I was just afraid every one was going to start hugging.

210.4(B) is in the top five worst code changes ever.
 

Strathead

Senior Member
See post # 20. It pays to read posts more than once some times.

And as an aside, protecting stupid and idiots is not a concern of mine, see the definition of "Qualified Person"

quote_icon.png
Originally Posted by iwire
I think we have here exactly the situation they have in the code making panels.

We have very knowledgeable, well meaning people that have little if, any hands on experience with a particular method deciding that they know better than the people that actually work with it based on 'what ifs'.




Roger


I have read this a couple of times and still read it the same way. iWire said, "We have..." which I interpretted as meaning the MIke Holt Forum. and the went on to describe the problem of knowledgeable people. I don't agree with this assesment of the Mike Holt Forum. If that is not what iwire meant, then he could easily clarify.

What am I reading wrong?

On the aside, I, like you, have no concern for protecting idiots either. I don't care for the handle tie code change, but that isn't what I was commenting on.
 

roger

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I have read this a couple of times and still read it the same way. iWire said, "We have..." which I interpretted as meaning the MIke Holt Forum. and the went on to describe the problem of knowledgeable people. I don't agree with this assesment of the Mike Holt Forum. If that is not what iwire meant, then he could easily clarify.

What am I reading wrong?
I'm not sure you're reading anything wrong, I have read it more times as well and can see your point, I'm sure Bob will let us know.

Roger
 

jumper

Senior Member
I have read this a couple of times and still read it the same way. iWire said, "We have..." which I interpretted as meaning the MIke Holt Forum. and the went on to describe the problem of knowledgeable people. I don't agree with this assesment of the Mike Holt Forum. If that is not what iwire meant, then he could easily clarify.

What am I reading wrong?

On the aside, I, like you, have no concern for protecting idiots either. I don't care for the handle tie code change, but that isn't what I was commenting on.

I'm not sure you're reading anything wrong, I have read it more times as well and can see your point, I'm sure Bob will let us know.

Roger

I just reread Bob's post, I am thinking Bob was taking a jab at Charlie B and the CMP members, not MH members as a whole.

Bob dislikes the 2008 MWBC handle tie rule change IIRC.
 

iwire

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Location
Massachusetts
I just reread Bob's post, I am thinking Bob was taking a jab at Charlie B and the CMP members, not MH members as a whole.

Not really a jab, just my view of the situation. The people making the rules have are not nessarilly that experienced with how electrians work in the field

Now I know they have some CMP members that are electrians but honestly I wonder how long it has been since these electricians actually worked with the tools?

Strathead, could you have made a bigger deal over my casual use of the word 'we'? I don't have editors go over my posts and I am not writing code sections so lighten up OK?
 

jumper

Senior Member
Not really a jab, just my view of the situation.

Sorry, poor wording on my part. I was only trying to clarify that your use of "we" was not meant as MH members as a whole per se, but as a general usage plural pronoun-non specific and not directly associative.

Crapola, did I just write that grammar crap? Darn wife is a librarian and English major!:)
 

Strathead

Senior Member
Strathead, could you have made a bigger deal over my casual use of the word 'we'? I don't have editors go over my posts and I am not writing code sections so lighten up OK?

Sorry! I didn't feel that my original, intended to be light hearted rebuttal of your original post was a big deal. It was the two comments by others that made me question whether I was reading is wrong and made me follow up with a more serious post. I just wasn't sure how serious you were since sarcasm doesn't come through the typed word very well.
 
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