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

[charlie b]

Thanks, Bob and Roger, for clarifying the nature of a "yoke." This has confirmed my earlier conjecture that "breaking off the bridge" does not turn a single yoke device into a two yoke device. That in turn confirms my statement that 210.21(B)(1) is not a player in the situation under discussion.

 

[iwire]

Thanks, Bob and Roger, for clarifying the nature of a "yoke." This has confirmed my earlier conjecture that "breaking off the bridge" does not turn a single yoke device into a two yoke device. That in turn confirms my statement that 210.21(B)(1) is not a player in the situation under discussion.

No it does not turn it into a two yoke device but a duplex is two receptacles broken bridge or not.

Receptacle. A receptacle is a contact device installed at the
outlet for the connection of an attachment plug. A single
receptacle is a single contact device with no other contact
device on the same yoke. A multiple receptacle is two or
more contact devices on the same yoke.

 

[maghazadeh]

A duplex is actually two receptacles so each individual receptacle is only receiving 120 volts.

infinity, I agree with duplex is two receptacles, but I don't agree that the two become individual things since both receptacles still is one device and the device is rated at 125V. Am I missing something here? If I am, then in my opinion the duplex recep. should not be marked as 125V rated. It should say 125/250V rated.
Let me explain it this way.
In reply # 28, There is a switch shown on the left side and let's assume sw is rated for 125V, Can you install this sws in a 277V circuit? if the answer is no,, that would be the end of our discussion.
If answer is yes, then we should be able to install a snap on breaker rated 125V for a 277V.
Or why don't we start installing a 125/250V, 1 phase loadcenter with snap on CB's to a 277/480V, 1 phase feeder?
Let's focus on the voltage rating of the duplex recep. device, rather than getting in to 15A or 20A, is it MWBC or not, is the house wife going to be shocked worst by 120V or 240V.

Voltage rating..........., voltage rating..................?????????

Again the question is the 125V rating written on a device that we call it duplex recep. is for the whole device or is it for each recep. in the duplex device.
If the whole device rated at 125V, then it should not be okey to wire it the way was descibed in the OP.

 

[Dennis Alwon]

Mag.. the only difference here is that the one device is now split into two separate units. There is still 125V on each individual part. 240v, imo is when there is two opposite phases on the same device. Of course this is just as I see it. The code is not clear on this issue imo.

 

[maghazadeh]

Mag.. the only difference here is that the one device is now split into two separate units. There is still 125V on each individual part. 240v, imo is when there is two opposite phases on the same device. Of course this is just as I see it. The code is not clear on this issue imo.

Dennis, Are you saying that when you install a duplex receptacle for disposal and dish washer, you either use;
(1) 120V circuit. (Duplex recieves 120V). or
(2) 120V cicuits with both cir. on phase "A" or both on phase "B". (Duplex recieves 120V). or
(2) 120V circuits with 1 cir. on phase "A", and 1 cir. on phase "B". (Duplex recieves 240V).

I think where our wires get crossed in our mind is I consider a duplex to be one device with two receptacles that the whole device is rated for 125V. But you are considering a duplex to be one device rated 125V with all bridges attached, and two separate devices rated 125V when bridges are removed.

 

[kwired]

Is there any meaning in 'minimizing electrical shock risk'or not?

Not using electricity is one way to minimize electrical shock risk:happyyes:

We can go back to washboards, wash tubs, drawing water from shallow wells with pails, or from lakes or streams.

Don't know how todays younger than 35 and in some cases younger than 65 would survive without their information technology devices though. I know I would give it all up for a simple life.

 

[George Stolz]

Dennis, Are you saying that when you install a duplex receptacle for disposal and dish washer, you either use;
(1) 120V circuit. (Duplex recieves 120V). or
(2) 120V cicuits with both cir. on phase "A" or both on phase "B". (Duplex recieves 120V). or
(2) 120V circuits with 1 cir. on phase "A", and 1 cir. on phase "B". (Duplex recieves 240V).

I think where our wires get crossed in our mind is I consider a duplex to be one device with two receptacles that the whole device is rated for 125V. But you are considering a duplex to be one device rated 125V with all bridges attached, and two separate devices rated 125V when bridges are removed.

According to the UL White Book, RTRT, duplex receptacles are listed for MWBC. 125V are suitable for a 120/240V MWBC.

 

[david]

Dennis, Are you saying that when you install a duplex receptacle for disposal and dish washer, you either use;
(1) 120V circuit. (Duplex recieves 120V). or
(2) 120V cicuits with both cir. on phase "A" or both on phase "B". (Duplex recieves 120V). or
(2) 120V circuits with 1 cir. on phase "A", and 1 cir. on phase "B". (Duplex recieves 240V).

I think where our wires get crossed in our mind is I consider a duplex to be one device with two receptacles that the whole device is rated for 125V. But you are considering a duplex to be one device rated 125V with all bridges attached, and two separate devices rated 125V when bridges are removed.

It is a duplex rec. when it left the manufacture, It is no longer a duplex receptacle when you alter it by braking one of the tabs. The tabs are designed to be broken for different applications there will be instructions from the manufacture showing different allowable wring configurations.

Nothing says you couldn’t install two duplex rec. in a two gang box and supply the two duplex rec, with a maltiwire branch circuit

Or supply the two duplex rec, with two separate branch circuits.

I guess what everyone is trying to convey is from a safty stand point the only way to address what you are stating is to submit a proposal asking for ( 6ft ) or some other dimension between appliances in a kitchen when the branch circuits supplying them have a different line to line potential

 

[Dennis Alwon]

Dennis, Are you saying that when you install a duplex receptacle for disposal and dish washer, you either use;
(1) 120V circuit. (Duplex recieves 120V). or
(2) 120V cicuits with both cir. on phase "A" or both on phase "B". (Duplex recieves 120V). or
(2) 120V circuits with 1 cir. on phase "A", and 1 cir. on phase "B". (Duplex recieves 240V).

I think where our wires get crossed in our mind is I consider a duplex to be one device with two receptacles that the whole device is rated for 125V. But you are considering a duplex to be one device rated 125V with all bridges attached, and two separate devices rated 125V when bridges are removed.

I am saying that I consider a duplex with the tabs broken to be a 2- single recep. That may not be the way an inspector looks at it but to me it is virtually the same except for the shared egc. IMO, art. 210.21(B)(1) would apply. I do not see an issue with a mwbc being used on this split duplex.

 

[infinity]

I am saying that I consider a duplex with the tabs broken to be a 2- single recep. That may not be the way an inspector looks at it but to me it is virtually the same except for the shared egc. IMO, art. 210.21(B)(1) would apply. I do not see an issue with a mwbc being used on this split duplex.

I agree.

 

[handy10]

I am saying that I consider a duplex with the tabs broken to be a 2- single recep. That may not be the way an inspector looks at it but to me it is virtually the same except for the shared egc. IMO, art. 210.21(B)(1) would apply. I do not see an issue with a mwbc being used on this split duplex.

I agree that what you are saying makes perfect sense and perhaps there is somewhere in the code that would give that definition. However, the definition in Article 100 for a receptacle reads "A single receptacle is a single contact device with no other contact device on the same yoke. A multiple receptacle is two or more contact devices on the same yoke."

 

[wwhitney]

I am saying that I consider a duplex with the tabs broken to be a 2- single recep.

For a duplex receptacle served by an MWBC, wouldn't the typical installation be to only break the tab on the hot side, and to leave the tab on the neutral side?

Cheers, Wayne

 

[Hv&Lv]

I am saying that I consider a duplex with the tabs broken to be a 2- single recep. That may not be the way an inspector looks at it but to me it is virtually the same except for the shared egc. IMO, art. 210.21(B)(1) would apply. I do not see an issue with a mwbc being used on this split duplex.

Wouldn't it HAVE to be like you described it with 240V between the receptacles in order to keep from overloading the neutral? Unless you were to run, for example, (2) 12-2WG to each receptacle. But then you have the problem of having two seperate breakers feeding the same receptacle. I thought in order to keep right with 210.4(B), there is no other way except to have 240 between the receptacles.

 

[George Stolz]

I am saying that I consider a duplex with the tabs broken to be a 2- single recep. That may not be the way an inspector looks at it but to me it is virtually the same except for the shared egc. IMO, art. 210.21(B)(1) would apply. I do not see an issue with a mwbc being used on this split duplex.

I think you've got this all wrong.

The definition of a MWBC clearly states it is a single circuit.

The definition of receptacle makes it clear that if a yoke features two devices, then it is a multiple receptacle.

Where are you coming up with two circuits with single receptacles?

A duplex with a disposal on phase A and a dishwasher on phase B is clearly not an individual branch circuit; 210.21(B)(1) does not apply.

 

[Dennis Alwon]

I think you've got this all wrong.

The definition of a MWBC clearly states it is a single circuit.

Where does it state that it is a single circuit. I don't see. It states it is a branch circuit (singular) but that is because it is a branch circuit- It is a mwbc. That does not mean it is a single circuit. If it were a single circuit then how do we install two separate breakers feeding two circuits. I disagree with you on 210.21 not applying. Think of the intent of the art. and can you honestly say that the intent is not to have a 20 amp individual circuit on one single receptacle. Forget the semantics and look at what they are trying to do. The purpose is to avoid a 20 amp circuit feeding a 15 amp single device.

We cab argue the semantics all day but I believe you would not win this one with most inspectors. A mwbc cannot be a single branch circuit and a mwbc at the same time. In some cases, as a dryer or range, the MWBC is just one circuit but other times it is a multiple circuit. The case we are talking about is utilizing multiple circuits.

 

[iwire]

Where does it state that it is a single circuit. I don't see. It states it is a branch circuit (singular) but that is because it is a branch circuit- It is a mwbc.

Right here

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.

That does not mean it is a single circuit.

I can't see how you would say that.

If it were a single circuit then how do we install two separate breakers feeding two circuits.

The number of overcurrent devices do not define the circuit.

If what you are saying was true an electric dryer circuit would be two circuits as it has two overcurrent devices.

We can argue the semantics all day but I believe you would not win this one with most inspectors.

That is the second time you have said that, IMO it is not semantics, it is exactly what the definition says.

A mwbc cannot be a single branch circuit and a mwbc at the same time.

So in your opinion what type of circuit(s) supply a typical electric range?

 

[maghazadeh]

All of you guys are wonderful, I really enjoy to see different opinions as posted here.
I think after stopping going elsewhere and focusing on the voltage rating of this issue I finally got the point more clearly, and I thank you for that.
Especial thanks to George Stolz for mentioning UL white book in reply # 46, Dennis Alwon, infinity, iwire, Charlie B, T.M. Haja Sahib, and on and on............!!! Sorry too many of you replied so hard to remember everyone but thank you all.
I like to take this opportunity and wish everyone a Merry Christmas and Happy New Year.
Hope to hear from all of you next year too.

 

[George Stolz]

Where does it state that it is a single circuit. I don't see. It states it is a branch circuit (singular) but that is because it is a branch circuit- It is a mwbc. That does not mean it is a single circuit.

Here, maybe this will help:

http://youtu.be/Wv6aksaqYuA

 

[Dennis Alwon]

That is the second time you have said that, IMO it is not semantics, it is exactly what the definition says.

It is semantics, IMO. The definition does not state it is a single circuit-- where does it say that? Show me the words in the definition that calls it a single circuit.

So in your opinion what type of circuit(s) supply a typical electric range?

I already answered that. In the case of a range it is a single circuit. Not all mwbc , imo are single circuits. As Roger stated 210.4 says that a mwbc shall be permitted to be considered as multiple circuits. Yet you say it is a single circuit. Okay--

I really don't want to argue this any further. I see 210.21(B) as applying in this case, if you don't fine, I have no problem with that.

 

[gndrod]

I feel I am getting caught up in the vortex of this MWBC discussion. I wish the NEC would come out and define MWBC as a circuit that can have a split phase property that is part of a single circuit. Once and for all.... a split phase is only part of an MWBC. Does that seem to make sense?
Getting back to terminology, isn't it reasonable that a split-wired duplex is not the same as a multi-wired duplex that has a 240v potential on the same yolk?