Supermarket Display Case ... Appliance? Disconnect?

[Gregg Harris]

There may still be a grey area as to whether they constitute an Appliance under NEC
If they do meet that criterion, then you may have to run a web of strings connecting breakers in different panels or something equally absurd to meet the grouped disconnect criterion.
I suppose if the entire aisle or row is considered one "appliance" then you could group the disconnects by having one motor panel, one lighting panel, etc. for each aisle placed compactly together and call it a grouping.
But once you put several aisles on one panel, the grouping becomes pretty tricky.

PS: The more I think about it, the more I would say that an individual case section would not be an appliance, but the whole aisle might be.... Or at least the whole part of the aisle that shares the same air space inside the doors.

440.3 Other Articles. (A) Article 430. These provisions are in addition to, or amendatory of, the provisions of Article 430 and other articles in this Code, which apply except as modified in this article.


(B) Articles 422, 424, or 430. The rules of Articles 422, 424, or 430, as applicable, shall apply to air-conditioning and refrigerating equipment that does not incorporate a hermetic refrigerant motor-compressor. This equipment includes devices that employ refrigeration compressors driven by conventional motors, furnaces with air-conditioning evaporator coils installed, fan-coil units, remote forced air-cooled condensers, remote commercial refrigerators, and so forth.


422.1 Scope. This article covers electrical appliances used in any occupancy.

 

[GoldDigger]

The rules of Articles 422, 424, or 430, as applicable, shall apply to air-conditioning and refrigerating equipment that does not incorporate a hermetic refrigerant motor-compressor. This equipment includes devices that employ refrigeration compressors driven by conventional motors, furnaces with air-conditioning evaporator coils installed, fan-coil units, remote forced air-cooled condensers, remote commercial refrigerators, and so forth.

All that says to me is that if they are in fact appliances, then the cited sections apply ("as applicable") rather than the separate provisions for internal hermetically sealed motor-compressor units. If they are not appliances, then none of them apply.

For example, if I have an HVAC engineer design a custom AC unit for a large building, picking compressors, valves, controls, evaporators, air handlers, etc. from a range of manufacturers and putting them together to make a system the result is not, to me, an appliance.
One characteristic of an appliance is that although it may require some PE, Refrigeration, or EE input to install properly, the bulk of the design work has been done already. And, of course the components come from one supplier regardless of who actually manufactured them.

 

[kwired]

All that says to me is that if they are in fact appliances, then the cited sections apply ("as applicable") rather than the separate provisions for internal hermetically sealed motor-compressor units. If they are not appliances, then none of them apply.

For example, if I have an HVAC engineer design a custom AC unit for a large building, picking compressors, valves, controls, evaporators, air handlers, etc. from a range of manufacturers and putting them together to make a system the result is not, to me, an appliance.
One characteristic of an appliance is that although it may require some PE, Refrigeration, or EE input to install properly, the bulk of the design work has been done already. And, of course the components come from one supplier regardless of who actually manufactured them.

Isn't each component still either an appliance, a motor, or air conditioning/refrigeration equipment as far as NEC is concerned? Or else some other major section of chapters 4, 5, or 6 applies, but the equipment in this discussion is generally one of those three.

I recently did an install of a boiler system with individual fan coils in rooms throughout the facility. It is all one system, but I used art 422 when running circuits for the fan coils, 422 for circuits to the boilers, 440 for the chiller, and 430 for the circulating pumps.