Does the NEC apply?

[charlie b]

I recently had a disagreement with an AHJ in California. We ultimately found a mutually acceptable solution. But I would like opinions on the original issue.

We are doing the electrical design for a restaurant. The designer of the kitchen equipment selected a table that had many different cooking capabilities. We were to supply a single set of conductors to a single point of connection. The table had a built-in enclosure with circuit breakers that served various points on the table. The table was UL listed.

The Inspector?s point of view was that,

• The internal components of the table fell within the scope of the NEC.
• The wires from our circuit breaker to the table comprised a feeder.
• The enclosure with the breakers comprised a panelboard as described in NEC article 408.
• The wires from that panelboard to each individual point on the table were branch circuits.
• The panel schedule that was provided by the table?s manufacturer was not acceptable as evidence of a calculation of the load that is to be served by the panelboard.
• The panel schedule and load calculation for this panelboard was therefore required to be issued with the project?s plans and specs, and was required to be signed and sealed by the project?s Designer of Record (i.e., us).

Our point of view was that,

• We were supplying branch circuit conductors to a UL listed appliance.
• The internal components of that appliance fell outside the scope of the NEC.
• No documentation of any wiring or load values associated with the appliance was required to be included in the project?s design documents.

Any comments?

 

[GoldDigger]

With you except maybe that as a branch circuit for a specific device you should know at least the maximum load the device represents.

 

[charlie b]

I think you mean that I should know what size of branch circuit to provide. They did state a MCA value. We used that and the information on their panel schedule as the basis for selecting the breaker and wires that supply the table.

 

[petersonra]

If it is a listed device my contention is that the listing is in of of itself evidence that it is a utilization device and thus the innards of the device are for the most part outside of the scope of the NEC.

 

[iceworm]

I recently had a disagreement with an AHJ in California. ...
Any comments?

Not a bit. I'm a woos. Anytime I get a 600lb ape with a badge and a gun stomping around I usually lay down and roll over. My norm is to lay out the code sections explaining my position. Follow that with my standard statement that this is good engineering design - we have no intent to build substandard. I wave my PE (which sometimes is like a red flag), and comment about how good the electricians are. If they are still brain locked - I'm fubared.

The table was UL listed.

Of course you were correct

We ultimately found a mutually acceptable solution. ...

No question - you da man.:thumbsup:

ice

 

[Dennis Alwon]

Our point of view was that,

• We were supplying branch circuit conductors to a UL listed appliance.
• The internal components of that appliance fell outside the scope of the NEC.
• No documentation of any wiring or load values associated with the appliance was required to be included in the project?s design documents.

Any comments?

I will agree with you totally on points one and two but I don't feel qualified to answer #3. It seems like the load should be included in the design but not sure about documentation

 

[augie47]

I'm in agreement with charlieb's point of view.
As an inspector I would look at the nameplate data and make sure your circuit was adequate and protected correctly.
IF I did have question or issue with the "appliance", i would advise you and then I would contact UL

 

[iwire]

I (we) install stuff like this all the time and I agree with Charlie.

I think the inspector is mistaken.

 

[Smart $]

I'm on the fence here (but many of you may feel it's not abnormal for me to butt heads ). To justify I'll point to:

• 90.4
• 90.7
• Approved definition
• 110.2

 

[Cow]

I don't see this as being much different than running a feeder to an air handler or furnace with a couple of 2 pole breakers factory installed in the unit.

 

[iwire]

I don't see this as being much different than running a feeder to an air handler or furnace with a couple of 2 pole breakers factory installed in the unit.

Exactly.

The ones I hook up are typically hot food bars with lighting, electric steam tables, soup wells, and heat lamps. There will be a panel under this unit with a listing label beside it. The label will show a MCA and max OCPD. The NEC stops at the units panel lugs.

If you tried to apply the NEC to the unit the panel itself is non-compliant due to 110.26 issues.

 

[cadpoint]

Does it directly reflect NEC requirements, only in respects that the Code asks us to do load calculations. How you or your company presents this information is subjective!

A lot of things can be stated or not stated in a panel schedule, some PE's can account for showing a circuit and it's load, some don't at all. Even if some information is just guessed at!

I think the AHJ has made a plan statement that your panel schedule does not show and account for the load of the the branch circuit in question!

In NC, some Counties require load summaries on drawing and are also used for qualifications of POCO electrical service, and it starts by this information showing in a panel schedules, which is than used in conjuction with permit applications.

Panel schedules are a PE little sercet, what they need to show when and what real information they are worth is always at least an objective summary!
Care to show your panel schedule of this job? (I'm joking)

I only comment on this because I heard back stories of how other's stole my EE's friends panel style!

 

[Sierrasparky]

I don't see this as being much different than running a feeder to an air handler or furnace with a couple of 2 pole breakers factory installed in the unit.

Exactly.

The ones I hook up are typically hot food bars with lighting, electric steam tables, soup wells, and heat lamps. There will be a panel under this unit with a listing label beside it. The label will show a MCA and max OCPD. The NEC stops at the units panel lugs.

If you tried to apply the NEC to the unit the panel itself is non-compliant due to 110.26 issues.

Charlie,
You are correct in your assertions. This is a UL listed device and nothing more than that of any other piece of equipment.

By the way was the product calculated properly or was there some fudging going on.

 

[captainwireman]

The UL listing should be the defining factor. If protection is adequate and approved by a testing lab, an overcurrent condition would result in operation of the overcurrent device. What if the client really had no idea if this particular operation would require far less or far more power in the future? Seems this variable should be factored into the demand of whatever table and both current and future use of said table may require and the appropriate size determined by these factors. If the table proves inadequate, at this time the customer will have to pay for upgrades. I disagree with the AHJ.

 

[charlie b]

I don't see this as being much different than running a feeder to an air handler or furnace with a couple of 2 pole breakers factory installed in the unit.

Precisely the example I raised with the inspector. His response was that the devices internal to the air handler were "supplemental overcurrent protection" (or perhaps he said "secondary overcurrent protection," I am not certain which), whereas the breakers in the table's panel were "primary overcurrent protection."

Throughout the five minute or so telephone conversation, I could tell that the inspector was moments away from closing the door by saying I could do whatever I wanted, but he would not approve the plans and issue the permit unless I did what he wanted. So I did not choose to pursue this point.

 

[charlie b]

The ones I hook up are typically hot food bars with lighting, electric steam tables, soup wells, and heat lamps. There will be a panel under this unit with a listing label beside it. The label will show a MCA and max OCPD.

That is exactly the type of table we are dealing with, and that is exactly the information that the manufacturer supplied.

The NEC stops at the units panel lugs.

I tried to point that out, but he would have none of it.

If you tried to apply the NEC to the unit the panel itself is non-compliant due to 110.26 issues.

I perceived that situation as well. I chose not to mention it.

 

[charlie b]

By the way was the product calculated properly or was there some fudging going on.

Good question. For starters, the load values were given in units of amps, not watts. So you have to know that there will be a problem with the calculation. Secondly, their panel schedule did not give the breaker ratings, nor was it clear whether any given load was supplied with a single pole breaker or a two pole breaker. Finally, it appears to me (again, I cannot be sure) that one particular load is being fed by a two pole breaker that connects to phases A and B. However, the load values stated on the schedule were 10 amps on phase A and 14 amps on phase B. Makes one wonder, doesn't it? :happyyes:

 

[cowboyjwc]

I recently had a disagreement with an AHJ in California. We ultimately found a mutually acceptable solution. But I would like opinions on the original issue.

We are doing the electrical design for a restaurant. The designer of the kitchen equipment selected a table that had many different cooking capabilities. We were to supply a single set of conductors to a single point of connection. The table had a built-in enclosure with circuit breakers that served various points on the table. The table was UL listed.

The Inspector?s point of view was that,

• The internal components of the table fell within the scope of the NEC. NO
• The wires from our circuit breaker to the table comprised a feeder. YES
• The enclosure with the breakers comprised a panelboard as described in NEC article 408. YES
• The wires from that panelboard to each individual point on the table were branch circuits. YES
• The panel schedule that was provided by the table?s manufacturer was not acceptable as evidence of a calculation of the load that is to be served by the panelboard. HMMMM
• The panel schedule and load calculation for this panelboard was therefore required to be issued with the project?s plans and specs, and was required to be signed and sealed by the project?s Designer of Record (i.e., us). YES

Our point of view was that,

• We were supplying branch circuit conductors to a UL listed appliance.
• The internal components of that appliance fell outside the scope of the NEC.
• No documentation of any wiring or load values associated with the appliance was required to be included in the project?s design documents.

Any comments?

So my answers are above in red. We have these pop up all the time. I have called UL on these things several times to find that they are not in fact listed (yet) and that some of the corrections I was calling were the same concerns that UL had. I have found these panels that had the neutrals and grounds bonded, I have had the panels two feet back inside of a stainless steel cabinet, non GFCI receptacles, etc. Why would you think that the load calculation would not be necessary on the plans. How would you know what to run and how would the inspector know what you were supposed to run? Or how would you know if the panel it was coming from was of sufficient size to carry the load?

Now as a disclaimer I was up until 3:00 this morning and am not running on all cylinders so I may have missed something.

 

[petersonra]

So my answers are above in red. We have these pop up all the time. I have called UL on these things several times to find that they are not in fact listed (yet) and that some of the corrections I was calling were the same concerns that UL had. I have found these panels that had the neutrals and grounds bonded, I have had the panels two feet back inside of a stainless steel cabinet, non GFCI receptacles, etc. Why would you think that the load calculation would not be necessary on the plans. How would you know what to run and how would the inspector know what you were supposed to run? Or how would you know if the panel it was coming from was of sufficient size to carry the load?

Now as a disclaimer I was up until 3:00 this morning and am not running on all cylinders so I may have missed something.

the op says the table was listed. are you claiming the listing is fraudulent?

 

[pfalcon]

UL listed appliance
Tampering with the device voids the UL listing
If inspector won't pass the device he needs to take it up with the design guy to select a different device