Open delta high leg identification requirement

[Spanky123]

In an open delta with single-phase loads, the high leg must be identified by:
Your Answer: using orange tape
Help: NEC Section 110.15

This was marked incorrect, but I do not understand how this is wrong after reviewing the NEC Section 110.15 It tells you to mark the high leg as orange.

[Kalbi_Rob]

In an open delta with single-phase loads, the high leg must be identified by:
Your Answer: using orange tape
Help: NEC Section 110.15

This was marked incorrect, but I do not understand how this is wrong after reviewing the NEC Section 110.15 It tells you to mark the high leg as orange.

After reading NEC 110.15, it seems like the question is not accurate, as it talks about a 4 wire Delta system in which one winding is grounded in the middle and a neutral is landed at that point. This would not be an open delta system as Open delta is a 3 wire system with B phase grounded.

[SecondGen]

After reading NEC 110.15, it seems like the question is not accurate, as it talks about a 4 wire Delta system in which one winding is grounded in the middle and a neutral is landed at that point. This would not be an open delta system as Open delta is a 3 wire system with B phase grounded.

Agree that this question should read 4-wire Delta system rather than open delta. As for the orange marking, 2015 edition states "orange in color or by other effective means."

Not sure what the other options are but "other effective means" implies that markings other than orange are still acceptable. Pic related.

[akumaleon]

Agree that this question should read 4-wire Delta system rather than open delta. As for the orange marking, 2015 edition states "orange in color or by other effective means."

Not sure what the other options are but "other effective means" implies that markings other than orange are still acceptable. Pic related.

In an open delta with single-phase loads, the high leg must be identified by:


tagging or numbering

using orange tape

using violet tape

any of the above


Are we agreeing that the question is wrong ? it should be 3-Phase /4wire and Orange is the marking?

[SecondGen]

In an open delta with single-phase loads, the high leg must be identified by:


tagging or numbering

using orange tape

using violet tape

any of the above


Are we agreeing that the question is wrong ? it should be 3-Phase /4wire and Orange is the marking?

Per NEC 110.15 (2017) it should be 4-wire delta, marking can be orange or "other effective means." Seems like tagging, numbering, or using any other color not prohibited by NEC (such as green) would be allowed.

[T-LOCC]

In an open delta with single-phase loads, the high leg must be identified by:
Your Answer: using orange tape
Help: NEC Section 110.15

This was marked incorrect, but I do not understand how this is wrong after reviewing the NEC Section 110.15 It tells you to mark the high leg as orange.

I did the same, its just a play with words to distract us.