All,

The type of equipment I am talking about is large capital equipment. It may have multiple power sources, it may be in several rooms, it may be outside. It may be for medical use, facility security, or factory automated manufacturing. I am just trying to understand where one set of requirements stop and the next set begin.

I'm looking for the equivalent of the demarcation point that separates the phone company equipment from the building's equipment.

Quote
If the equipment is manufactured in "an engineered controlled environment", then the NEC does not apply.


I interpret that to mean, If we design and build it, and then oversee the installation of it in your facility, the NEC applies up to the Main disconnect(s) and everything past that falls on the machine designer/builder.

If there are multiple equipment cabinets connected to sub assemblies and each other, by cables laying in dedicated cable trays, are the cables subject to NEC requirements too? The power flowing thru the cable tray cables come from power supplies that are downstream of the disconnects.

Thanks for all of the replies so far.