One (1) duplex receptacle for disposal and dish washer?

[kwired]

I don't evem know what that means



So under the 2005 NEC before I was required to tie the handle ties to gather i run potential multi wire circuit to two rec. in a two gang box I close the breaker for line one but I leave the breaker for line to open. My garbage disposal is tied to line one but I don?t own a dishwasher. So I have a 20 amp 120 volt circuit. After working on my disposal I plug it into the rec. that is feed from line two this breaker is in the open position , so my disposal doesn?t work. Am I plug in to a branch circuit or not.

Line one meets the definition of a branch circuit with the breaker in the closed position
Line two meets the definition of a branch circuit with the breaker in the open position
Neither one of these circuits meets the definition of a multiwite branch circuit until I close both line one and line two breakers.
Line one and line two are two 20 amp branch circuits working independent of each other

Even now you can still have one line with breaker closed and other line with breaker tripped and a handle tie between them and still have mostly the same thing you described and it is still called a MWBC.

Requiring the handle ties did not change what is a MWBC, it changed how a MWBC is to be disconnected from the supply voltage.

 

[George Stolz]

I don't evem know what that means

It means your argument that a multiwire branch circuit is always two circuits is predicated on the concept that they didn't think about the possibility of MWBCs when they wrote sundry sections of code. It would take a TCC to sort it all out and make the language jive, but that doesn't undo the basic concept; a MWBC is a circuit.

You are pointing to omissions as proof that the definition is wrong, unless I misunderstand you.

Am I plug in to a branch circuit or not.

Are you asking if a branch circuit ceases to be a branch circuit if you open the breaker? :?

 

[david]

Even now you can still have one line with breaker closed and other line with breaker tripped and a handle tie between them and still have mostly the same thing you described and it is still called a MWBC.

Requiring the handle ties did not change what is a MWBC, it changed how a MWBC is to be disconnected from the supply voltage.

Branch Circuit. The circuit conductors between the final overcurrent device protecting the circuit and the outlet(s).
Branch Circuit, Multiwire. A branch circuit that consists of two or more ungrounded conductors that have a voltage between them, and a grounded conductor that has equal voltage between it and each ungrounded conductor of the circuit and that is connected to the neutral or grounded conductor of the system.


With or without a voltage between line one or line two you meet the definition of a branch circuit the definition of a branch circuit only makes reference to the conductors of the circuit
The definition of a multiwire branch circuit has to have a voltage between the conductors to meet the definition.
So both line one and line to meet the definition of a branch circuit with out consideration to to a voltage potential. So line one and line two are branch circuits no matter what but the do not meet the definition of a multiwire branch circuit until there isa voltage between the conductors

 

[david]

When you have line one and line two that work independent of each other and the code says that a multi wire circuit can be considered two circuits. A disconnecting means under 2005 had to disconnect all ungrounded conductors of a circuit. And two independent 20 amp breakers back in 2005 did not disconnect both line one and line two together. How could these not be two circuits.

 

[david]

LOL
Since we are getting close to Christmas I think I’ll take this thread to a pastor of a nearby church and he can use a multi wire circuit to illustrate the trinity when it comes to the Christian faith. One God three persons
Considered one but also considered separate
Maybe line one could illustrate God
Line Two Christ
The neutral the Holy Spirit
I hope no one is offended by that if your are sorry, but lighten up it only made me laugh when I thought of the parallel

 

[George Stolz]

When you have line one and line two that work independent of each other and the code says that a multi wire circuit can be considered two circuits. A disconnecting means under 2005 had to disconnect all ungrounded conductors of a circuit. And two independent 20 amp breakers back in 2005 did not disconnect both line one and line two together. How could these not be two circuits.

Perhaps, due to the fact that the MWBC was one circuit, people were getting shocked from the grounded conductor of that one circuit when one leg was energized.

I'll give you a chuckle for the joke - Merry Christmas to you!

 

[david]

Perhaps, due to the fact that the MWBC was one circuit, people were getting shocked from the grounded conductor of that one circuit when one leg was energized.

I'll give you a chuckle for the joke - Merry Christmas to you!

I am not arguing it is not a multi-wire circuit,

But it also is allowed to be considered two circuits.

Further the allowance would have had to be implemented when the disconnecting means of the multi-wire branch circuit, was done with two independent 20 amp breakers disconnecting the line one and line two conductors. If line one ?natural and line two- neutral are not two 20 amp branch circuits would you not expect to see a single disconnecting means instead of two separate disconnecting means for the un-grounded conductors? So in this circumstance the allowance is more than permissive, does not the existence of two single pole breakers that where code compliant disconnects in 2005 mandate that these are two branch circuit disconnects.

 

[George Stolz]

I am not arguing it is not a multi-wire circuit,

But it also is allowed to be considered two circuits.

Further the allowance would have had to be implemented when the disconnecting means of the multi-wire branch circuit, was done with two independent 20 amp breakers disconnecting the line one and line two conductors.

Show me the mechanism in the NEC that changes the "shall be permitted" to the "shall be" and you win the argument.

In 2002 there was no requirement to tie the handles, and to this day there is no requirement for common trip - you are making a leap that the NEC does not require you to make. This is similar to the idea that all outlets within 6' of a source of water require GFCI protection; that prior to 2008 drinking fountains required GFCI protection; that ground rods have to be no more than 6' apart; that a can 10' over the rim of a bathtub requires a shower trim; the list goes on.

These are all misconceptions that many will defend to the death, despite the fact that they are either entirely wrong or slight misinterpretations of the actual wording of the NEC.

This same flavor of thinking is coloring your take on this issue, IMO. Charlie's Rule: read it again, please.

 

[hurk27]

This same flavor of thinking is coloring your take on this issue, IMO. Charlie's Rule: read it again, please.

Ok lets use Charlie's rule on this:
210.21(B)(1):

(B) Receptacles.
(1) Single Receptacle on an Individual Branch Circuit.
A single receptacle installed on an individual branch circuit
shall have an ampere rating not less than that of the branch
circuit.

As per article 100:

Branch Circuit, Individual. A branch circuit that supplies only one utilization equipment.

So a multiwire circuit might be a single circuit but it is not a Individual Branch Circuit when supplying more then one load as per the NEC and 210.21(B)(1) clearly states "Individual Branch Circuit" applying Charlie's rule, it is what it is:happyyes:

Might have been the reason they choose the Individual Branch Circuit instead of a single branch circuit as is done in many other places in the NEC?

 

[hurk27]

if we look at the wording of 230.79(A) (there are other places I could also use as an example also)

(A) One-Circuit Installation. For installations to supply only limited loads of a single branch circuit, the service disconnecting means shall have a rating of not less than 15 amperes.

We can clearly see that a MWBC would fit right into this from the definition of a MWBC.

I have also learned new from this thread that there is a difference between a Individual branch circuit and a single branch circuit, I never realized this before until I saw it in the definition.:happyno:

 

[kwired]

LOL
Since we are getting close to Christmas I think I?ll take this thread to a pastor of a nearby church and he can use a multi wire circuit to illustrate the trinity when it comes to the Christian faith. One God three persons
Considered one but also considered separate
Maybe line one could illustrate God
Line Two Christ
The neutral the Holy Spirit
I hope no one is offended by that if your are sorry, but lighten up it only made me laugh when I thought of the parallel

I would find it interesting in some churches to actually do that just to see if anyone was really paying attention to the sermon:happyyes:

 

[deerhunter]

2 pole breaker

2 pole breaker

It should be a 20 amp duplex receptacle (hotside split) and because it is on A&B phase it requires a 2 pole breaker.

 

[BullsnPyrs]

and the Master Electrician who trained me required 2 - 20 amp single receptacles on an industrial cover clearly labeled for dishwasher and disposal. Not the cheapest installation but clean and profesional in apearance.

 

[John120/240]

and the Master Electrician who trained me required 2 - 20 amp single receptacles on an industrial cover clearly labeled for dishwasher and disposal. Not the cheapest installation but clean and profesional in apearance.

What makes two single 20 receptacles better than one duplex recptacle ? Yes I understand

that in one situation you have two yokes vs one yoke.