A-B-C or L1-L2-L3

[publicgood]

I understand these are used interchangeably. Curious though if there is a NEMA, ANSI, IEC, IEEE, or other standard based on equipment type or voltage? NEC 408.3(E) states A-B-C for arrangement...

 

[Jraef]

A-B-C are the conductors / phases etc. L1, L2, L3 are the terminals designation on the line side of the equipment, as opposed to T1, t2, t3 on the load side. If you just used A-B-C on the equipment, you would not be able to easily determine which side is line and which is load. Also, A-B-C is relative only to one another. L1, L2, L3 is absolute, L1 is on the left, L2 in the middle, l3 on the right as you face it. THAT is in the code. L1 2 3 left to right, top to bottom.

 

[LarryFine]

A-B-C or L1-L2-L3

". . . as simple as do-re-mi . . ."

 

[cowboyjwc]

[/COLOR]
". . . as simple as do-re-mi . . ."

"I blow through here
The music goes 'round and around
Whoa-ho-ho-ho-ho-ho
And it comes out here"

 

[publicgood]

THAT is in the code. L1 2 3 left to right, top to bottom.

408.3(E) uses A-B-C to describe left to right, front to back, and top to bottom - not L1, L2, L3.