Labeling Delta Panels

[inspector 102]

Is there a requirement for labeling a three-phase delta panel? I have always seen it, but never checked for requirements. Apparently 2 electricians are arguing the requirement and I do not know where to find the answer yes or no? Any help appreceiated.

 

[rcarroll]

'08 nec 408.3(f)

 

[celtic]

408.3(F) in the '08.

 

[charlie b]

Is there an echo in here?

 

[jim dungar]

'08 nec 408.3(f)

This is applicable, only if it is a center tapped delta, 240/120 3P 4W.

A corner-grounded or an un-grounded delta panel do not require any special marking.

 

[rcarroll]

This is applicable, only if it is a center tapped delta, 240/120 3P 4W.

A corner-grounded or an un-grounded delta panel do not require any special marking.

Thanks for the clarification. :smile:

 

[mpd]

I know what the purpose of this label is, but is it really necessary, does anybody know what prompted this change?

 

[augie47]

I know what the purpose of this label is, but is it really necessary, does anybody know what prompted this change?

I would guess the number of instances where a 120 volt load was connected to the hi-leg. Many an electrician has learned the hard way.

 

[mpd]

I would guess the number of instances where a 120 volt load was connected to the hi-leg. Many an electrician has learned the hard way.

I always thought you were taught to test first and when you see a electrical panel with every 3rd space blank, it should alert you to use your tester first

 

[augie47]

Not all of us do what we were taught

Each Code cycle seems to add articles supporting that sad fact.

 

[mpd]

Not all of us do what we were taught

Each Code cycle seems to add articles supporting that sad fact.

very true, NEC seems to be increasing the amount of labeling each code cycle

 

[MarkyMarkNC]

I wish this had been a code 15 years ago when the fan I hooked up on a high leg started blowing crop circles in that poor ladies rug.:grin:

 

[mpd]

I wish this had been a code 15 years ago when the fan I hooked up on a high leg started blowing crop circles in that poor ladies rug.:grin:

but would you have read it? or even noticed it? if you see an arc flash warning label do you still work the panel hot? just curious how many people actually read a field applied label or are they just for the lawyers & insurance companies

 

[e57]

I would guess the number of instances where a 120 volt load was connected to the hi-leg. Many an electrician has learned the hard way.

I have marked hi-leg panels maybe 10 different ways, I think it only matters if you are paying attention - or if the signage is REALLY BIG!

One building in particular got three different guys over the course of 8 years - IMO it finally came down to the client was always rushing people through the work. We would send well qualified guys, but the client (a wood shop owner) had three different systems in the building, a corner grounded delta, a hi-leg and 480wye - two services from the street and one T inside. He would meet you at the door, then micro manage over the shoulder of anyone we sent though every moment of any equipment he needed installed. As the 'go-to' foreman - I was also the go-to "Cooler" for the company, and after several incidents there I realized it was the client rushing the job, and just generally tensing out anyone we sent - the result being things blowing up - going in reverse or just generally not working. WHY? Because from the moment you walk in the door - it was hard to think about anything past what a PILL and task master he was. I'd often find myself thinking just that - then step back in my mind and realize that I too was about to blow something up.... Even though I had marked many of the panels in the building myself.