Supervised Industrial Installation

[Steelhead]

In 240.2 (2) (of the 2011 NEC) what is the importance of 2500 KVA of load?

Also, in determining the load required in that section, would I use the nameplate current rating of the equipment involved in the manufacturing and processing activities or would I use the actual load imposed?

 

[augie47]

The importance is that it allows you to use Part VIII of Art 240 which is a bit more lenient on some overcurrent requirements.
I would say you would use the Art 220 calculated load which would include your nameplate loads.

 

[Steelhead]

The importance isthat it allows you to use Part VIII of Art 240 which is a bit more lenient on some overcurrent requirements.
I would say you would use the Art 220 calculated load which would include your nameplate loads.

Ok, but why 2500 KVA and not 3500 KVA? I'm just curious as to why that particular number.

 

[iceworm]

Ok, but why 2500 KVA and not 3500 KVA? I'm just curious as to why that particular number.

Yes, interesting question. One might think that item 1 (only qualified persons) was enough.

side note:
Why "engineering supervision" would matter completely baffles me. My inclination is "conditions of management committment" does more to ensure qualified persons than anything else.
​

Following is a blind guess:
Code panel thinks that item 2, (2500kVA) and item 3 (at least one 480V or 575V , or MV feeder) makes it more likely that management will continue to pay for qualified persons.

As to why 2500kva as opposed to 1500kva or 3500kva?
Don't know. Looks right up there with the ouiji board selected 25 ohms. This was new with the 1999 code. I'm sure the panel underwent severe negotiation.

ice

 

[kwired]

As to why 2500kva as opposed to 1500kva or 3500kva?
Don't know. Looks right up there with the ouiji board selected 25 ohms. This was new with the 1999 code. I'm sure the panel underwent severe negotiation.

ice

...and came to no consensus so they went with the ouija board to come up with a final figure:happyyes:

Now if we could get lawmakers to do the same we would at least get out of deadlock on many issues:angel:

 

[iceworm]

...and came to no consensus so they went with the ouija board to come up with a final figure:happyyes:

Now if we could get lawmakers to do the same we would at least get out of deadlock on many issues:angel:

possibly

yes

ice