Dedicated Circuit Question

[franklinmanklin]

3-Pole Breaker, one utilization equipment ~ Is it considered a dedicated circuit?

Also, should the neutral be considered to count as to the fact if it is dedicated or not, in the case whereas the neutral is shared but the circuits are not on a breaker of a shared yoke (meaning 2- or 3-poles).

 

[Dennis Alwon]

That is considered one circuit, IMO, The neutral in this case does not make a difference

 

[jumper]

If nothing else is connected, but one piece of equipment, then you have an individual/dedicated circuit.

I do not think the neutral is counted as a CCC in this case.

 

[Dennis Alwon]

If nothing else is connected, but one piece of equipment, then you have an individual/dedicated circuit.

I do not think the neutral is counted as a CCC in this case.

I thought the op was asking if the neutral counted in determining whether it was an individual circuit.

 

[jumper]

We are talking about a 3 phase piece of equipment, right?

 

[jumper]

I thought the op was asking if the neutral counted in determining whether it was an individual circuit.

Heck, I dunno, now I confused on exactly what the question is.

 

[Dennis Alwon]

We are talking about a 3 phase piece of equipment, right?

My understanding is it is a 3 phase piece of equipment with a neutral. The op had 2 questions. First was wether this was an individual circuit and the second was whether the neutral may change the fact making it 3 circuits. That is my take.

If the circuit is a 3 phase machine with a neutral then it is one circuit. Now a neutral being shared for 3 circuits going to lighting may not be considered one circuit. We have argued this and in some areas of the code a MWBC is considered one circuit.

 

[franklinmanklin]

Maybe This Will Clear It Up!

Maybe This Will Clear It Up!

The equipment being supplied is an ATM, 120V. The ATM company wants a dedicated circuit but it is fed with a 3-pole breaker. It is not my job to verify but to verify whether an employee verified it (if that makes any sense). Personally, I would remove the 3-pole breaker, pull in a new neutral, put this circuit on its own 1-pole breaker and put in a 2-pole breaker for the remaining circuits.

Technically, if the receptacle to be used doesn't share any other loads it IS considered dedicated (Branch Circuit, Individual) but you are asking for trouble and I wish that the definition stated dedicated line AND neutral.

 

[jumper]

I am going to call it a individual/dedicated circuit for this application.

210.4 Multiwire Branch Circuits.
(A) General. Branch circuits recognized by this article shall
be permitted as multiwire circuits. A multiwire circuit shall be
permitted to be considered as multiple circuits. All conductors
of a multiwire branch circuit shall originate from the same
panelboard or similar distribution equipment.

 

[Dennis Alwon]

Unless the equipment requires a dedicated neutral then I don't see an issue. If the neutral is used for the 3 circuits then it must be on a 3 pole breaker. Sometimes it does make sense to pull a separate neutral but that does not necessarily change the status of them being considered individual circuits.

 

[dkidd]

then it must be on a 3 pole breaker.

Or use handle ties.

 

[charlie b]

I am still confused over the installation. Are you saying that a 3-pole breaker serves more than one piece of equipment, with each of the three phase conductors serving only one piece of equipment, and with a shared neutral? Is this, in fact, a MWBC? If so, then I would say this does not meet the definition of, ?Branch Circuit, Individual,? as provided in Article 100. Please note that the NEC does not define ?Dedicated Branch Circuit,? so for clarity let us stick with the phrase ?individual branch circuit.?

My reasoning starts with the fact that a ?branch circuit? is defined in terms of wires only. The breaker is not part of the branch circuit, and neither is the load. At least, that is how the Article 100 definition of ?branch circuit? is worded. So a three phase MWBC will have four wires, and all four of them are part of the branch circuit. So if the phase A wire and the N wire serve one load, and if the phase B wire and the neutral serve a second load, and if the phase C wire and the neutral serve a third load, then the branch circuit, as a whole, serves more than one load. So it is not an individual branch circuit.

One more thing I would like to bring up. Do I understand that the ATM will plug into a standard duplex receptacle outlet? If so, then even if you used a single pole breaker, and ran a separate neutral serving just that one receptacle, I could argue that this is not an individual branch circuit. A duplex receptacle is not a piece of ?utilization equipment,? and two pieces of utilization equipment can be served by that singe branch circuit.

 

[charlie b]

Sometimes it does make sense to pull a separate neutral but that does not necessarily change the status of them being considered individual circuits.

I think it does. Having a 3-pole breaker, as opposed to three 1-pole breakers, is not relevant. But if a neutral is shared, then you no longer meet the definition of an individual branch circuits. More to the point, you don't have three "individual branch circuits." Looking at the article quoted by Jumper, the NEC permits us to consider a MWBC as being "multiple circuits." This not the same thing as considering them "multiple individual branch circuits." The distinction is that the neutral conductor serves more than one utilization equipment, even if the phase conductors do not, and that is enough to take us outside the definition of "branch circuit, individual."

 

[Dennis Alwon]

I think it does. Having a 3-pole breaker, as opposed to three 1-pole breakers, is not relevant. But if a neutral is shared, then you no longer meet the definition of an individual branch circuits. More to the point, you don't have three "individual branch circuits." Looking at the article quoted by Jumper, the NEC permits us to consider a MWBC as being "multiple circuits." This not the same thing as considering them "multiple individual branch circuits." The distinction is that the neutral conductor serves more than one utilization equipment, even if the phase conductors do not, and that is enough to take us outside the definition of "branch circuit, individual."

Well you may be correct but I never read it that way. I rarely use MWBC but I see what you mean. The neutral takes the individuality from it. I wonder if that is the intent when a piece of equipment comes in requiring an individual branch. So is a dedicated circuit the same as an individual circuit? I see them as the same

 

[franklinmanklin]

I am still confused over the installation. Are you saying that a 3-pole breaker serves more than one piece of equipment, with each of the three phase conductors serving only one piece of equipment, and with a shared neutral? Is this, in fact, a MWBC? If so, then I would say this does not meet the definition of, ?Branch Circuit, Individual,? as provided in Article 100. Please note that the NEC does not define ?Dedicated Branch Circuit,? so for clarity let us stick with the phrase ?individual branch circuit.?

My reasoning starts with the fact that a ?branch circuit? is defined in terms of wires only. The breaker is not part of the branch circuit, and neither is the load. At least, that is how the Article 100 definition of ?branch circuit? is worded. So a three phase MWBC will have four wires, and all four of them are part of the branch circuit. So if the phase A wire and the N wire serve one load, and if the phase B wire and the neutral serve a second load, and if the phase C wire and the neutral serve a third load, then the branch circuit, as a whole, serves more than one load. So it is not an individual branch circuit.

One more thing I would like to bring up. Do I understand that the ATM will plug into a standard duplex receptacle outlet? If so, then even if you used a single pole breaker, and ran a separate neutral serving just that one receptacle, I could argue that this is not an individual branch circuit. A duplex receptacle is not a piece of ?utilization equipment,? and two pieces of utilization equipment can be served by that singe branch circuit.

I could put a single receptacle in, would that qualify for the 'utilization equipment' or doesn't it matter. I guess I will contact the ATM company and see if they require it to be hard-wired and a dedicated neutral.

 

[jumper]

I think it does. Having a 3-pole breaker, as opposed to three 1-pole breakers, is not relevant. But if a neutral is shared, then you no longer meet the definition of an individual branch circuits. More to the point, you don't have three "individual branch circuits." Looking at the article quoted by Jumper, the NEC permits us to consider a MWBC as being "multiple circuits." This not the same thing as considering them "multiple individual branch circuits." The distinction is that the neutral conductor serves more than one utilization equipment, even if the phase conductors do not, and that is enough to take us outside the definition of "branch circuit, individual."

Aw Phooey, I had this one..............durn train driver.............

 

[charlie b]

I could put a single receptacle in, would that qualify for the 'utilization equipment' or doesn't it matter. I guess I will contact the ATM company and see if they require it to be hard-wired and a dedicated neutral.

If a receptacle outlet is the method of connecting the load, and if the client requires a "branch circuit, individual," then I think the only choice is a single pole breaker, a separate neutral, and a simplex receptacle.

 

[Dennis Alwon]

I guess I will contact the ATM company and see if they require it to be hard-wired and a dedicated neutral.

That is what I would do. If the company wanted a dedicated neutral then I would think they should say that. Of course if a neutral is opened on a mwbc you will put 240V to the machine so it is probably a good idea to have a separate neutral.

 

[charlie b]

So is a dedicated circuit the same as an individual circuit? I see them as the same

The only difference I see between those two phrases is that the first is unofficial, and is a "common conversational English" phrase, whereas the second has an official NEC definition. I think they can be used interchangeably, but as is often the case we need to be sure we are communicating clearly when we use the unofficial version.

 

[Dennis Alwon]

The only difference I see between those two phrases is that the first is unofficial, and is a "common conversational English" phrase, whereas the second has an official NEC definition. I think they can be used interchangeably, but as is often the case we need to be sure we are communicating clearly when we use the unofficial version.

I agree and many pieces of equipment I see state dedicated circuit not individual circuit. I wonder if the manufacturers really are calling for a circuit with nothing else on it. Even a separate circuit could be considered a dedicated neutral so it would appear a clarification may be in line.