Fuel Panel

[jap]

The problem is we are dealing with 2 different things that are very similar.

The Subpanel has roughly 6 single pole Cutler Hammer BAB-C Switched Neutral Breaker and 6 2p 20amp Breakers in it.
All of these satisfy the requirement of disconnecting means.
The Single poles open the neutral when shut off and the 2p breakers feed onlly 240v loads so they are fine also.

Now for the Emergency Power Off. (If your planning on using a single pushbutton shut everything down)

To be able to shut off all the power coming out of the Subpanel you would either have to shunt trip the 1p Switched Neutral Breakers (Which I dont think they even make one) along with providing shunt trip coils for the 2p breakers and daisy chain the shunt trips all together so the EPO would kill them all, or, install a Shunt Trip in the Feeder Breaker feeding the Subpanel (But then you'd have to use one pole of the breaker to switch the Neutral ) or install a Contactor on the Line Side of the Feeder to the Subpanel and open the Neutral also or install a Contactor on the Load side of the Subpanel and run all the circuits through them or your goiing to have to install some type of manual disconnect.

My questiion is does the same rule apply for the Emergency Power off as for the Requirement for disconnecting the Neutral along with the Circuit Conductors for Maintenance Means?

 

[kwired]

I can see a possible source of confusion here, in that one could see the function of the EPO as being solely to stop the machinery from operating (the common understanding) or also to also remove all sources of power in the event of a fire of electrical origin.
The latter function would, strictly speaking, require interrupting the neutral too if (big if) there is a neutral fault somewhere in the system that has applied voltage to the neutral.
I am not arguing for this, just suggesting that this inspector may have that incorrect understanding (or, of course, have no understanding at all. )

It does not, but I don't think the OP has clarified how many circuits run to each dispenser.

If there is only one circuit to each disperser I agree the breaker alone may satisfy 514.11

However if there is more than one circuit per dispenser the breakers do not provide a simultaneous means of disconnection, therefore in the OPs case the EPO will have to do that job and it will have to open the neutral.

514.11(B) or (C) refers you back to (A) which requires everything.
The real rub here is the new language in 2011 that makes it clear that "everything" even includes data, video, etc. Right now there are very few products available to accomplish this.

Ok I agree with you on what it says, I should have probably read it first before posting earlier:slaphead:

But I think it is self contradicting. It needs to better clarify if it wants a disconnect or a control. Part A for the most part is requirements for a disconnecting means. The parts in B and C that refer you back to A are calling it a control but sending you back to information on a disconnecting means.

 

[texie]

The problem is we are dealing with 2 different things that are very similar.

The Subpanel has roughly 6 single pole Cutler Hammer BAB-C Switched Neutral Breaker and 6 2p 20amp Breakers in it.
All of these satisfy the requirement of disconnecting means.
The Single poles open the neutral when shut off and the 2p breakers feed onlly 240v loads so they are fine also.

Now for the Emergency Power Off. (If your planning on using a single pushbutton shut everything down)

To be able to shut off all the power coming out of the Subpanel you would either have to shunt trip the 1p Switched Neutral Breakers (Which I dont think they even make one) along with providing shunt trip coils for the 2p breakers and daisy chain the shunt trips all together so the EPO would kill them all, or, install a Shunt Trip in the Feeder Breaker feeding the Subpanel (But then you'd have to use one pole of the breaker to switch the Neutral ) or install a Contactor on the Line Side of the Feeder to the Subpanel and open the Neutral also or install a Contactor on the Load side of the Subpanel and run all the circuits through them or your goiing to have to install some type of manual disconnect.

My questiion is does the same rule apply for the Emergency Power off as for the Requirement for disconnecting the Neutral along with the Circuit Conductors for Maintenance Means?

Yes, that is the point I have been trying to make.

 

[wwhitney]

The Subpanel has roughly 6 single pole Cutler Hammer BAB-C Switched Neutral Breaker and 6 2p 20amp Breakers in it.
All of these satisfy the requirement of disconnecting means.
The Single poles open the neutral when shut off and the 2p breakers feed onlly 240v loads so they are fine also.

It wouldn't help you with your installed equipment, but I was curious whether one could use a 3 phase panel for this application, treating the neutral as the third pole. Then the shunt trip main breaker would disconnect the neutral.

Cheers, Wayne

 

[jap]

It wouldn't help you with your installed equipment, but I was curious whether one could use a 3 phase panel for this application, treating the neutral as the third pole. Then the shunt trip main breaker would disconnect the neutral.

Cheers, Wayne

Thanks but no Thanks.

 

[wwhitney]

Thanks but no Thanks.

Oh, I wasn't making a suggestion, I was just curious if that would be an NEC compliant solution, or if there is some problem with using a 3 phase panel in that fashion.

Cheers, Wayne

 

[kwired]

Oh, I wasn't making a suggestion, I was just curious if that would be an NEC compliant solution, or if there is some problem with using a 3 phase panel in that fashion.

Cheers, Wayne

To see this would make many balk at whether or not it is acceptable, but it should be acceptable.

It probably happens more often with a corner grounded delta system. But in that case the grounded conductor is not a neutral conductor, but is still the system grounded conductor. Breakers in such instance need rated full 240 or full 480 volts and ones rated 120/240 or 277/480 would not be acceptable, but I don't see why that should be a problem with a true neutral as the grounded conductor that is being passed through the breaker, the voltage to ground is still within the rating of the breaker.