240V power supply wiring diagram

[jimbo3123]

Bruce,

You are correct regarding the NFPA-79 and 120VAC maximum control circuits. The 1997 edition of the standard reads about the same as the 2002 edition.

However, I know that NEMA starters are available with a variety of coils, including 460/480VAC and 575/600VAC. NEMA starters usually provide terminals on the top of the first two line side lugs for that purpose. I can only speculate that this was permitted under older versions of NFPA-79, or is used in applications where that standard does not apply (not industrial machinary).

Maybe someone can fill in some more details.

 

[rsdoran]

Due to unforeseen circumstances I am missing page 21 of NFPA 79 which has between 8.15 and 9.6. This is the section y'all are discussing right now.

If anyone could scan a copy of that section and send to me I would appreciate it.

 

[Lancie1]

NEC/NFPA is applicable to any electrical applications in the US. OSHA states both NEC and NFPA 79 as the standard(s) to use. Insurance inspectors also use NEC/NFPA 79 as their reference.

Ron,
There are some important exceptions in the US that the National Electrical Code does NOT cover. See "N.E.C. 90-2 Scope". These include ships, watercraft, railway rolling stock, aircraft, automotive vehicles, mines and mining machinery, telephone equipment, and electric utility installations.

Having done engineering work for an electric utility, I have often been told, "Well, yes, that is what it says in the N.E.C., but WE do it this way."

The N.E.C. does cover carnivals, however.

 

[DaMan]

240V into the PLC?

Heck,

He's gonna let the smoke out!!!! <very hard to get back in!>