Arc Flash Forum
https://brainfiller.com/arcflashforum/

Labeling of MV Pad Mount Distribution Transformers
https://brainfiller.com/arcflashforum/viewtopic.php?f=24&t=5352
Page 1 of 1

Author:  garydounson [ Mon Aug 24, 2020 8:11 am ]
Post subject:  Labeling of MV Pad Mount Distribution Transformers

Should a pad mount medium voltage distribution transformer have two separate arc flash labels; one for the high voltage compartment (Warning Label with high voltage and low incident energy) and one for the low voltage compartment (Danger Label with low voltage and high incident energy)? Should the information be combined into a single "Danger" label that lists the higher voltage and the higher incident energy?

Author:  mpparent [ Mon Aug 24, 2020 11:25 am ]
Post subject:  Re: Labeling of MV Pad Mount Distribution Transformers

While not an answer...you might look at the supplemental information in the NESC regarding AF and pad mount transformers. AF may not be high on the secondary. Use at your discretion.

Mike

PS <link to commercial website>. Somewhat outdated but I think relevant for discussion.

Author:  garydounson [ Tue Aug 25, 2020 11:39 am ]
Post subject:  Re: Labeling of MV Pad Mount Distribution Transformers

Hello Mike,

Thank you for the feedback. Yes, I see in NESC Table 410.1 the arc flash incident energy is substantially less for Pad Mount transformers than what the short -circuit study was indicating. Would two labels still be needed due to the different voltages associated with the high and low voltage compartments of the transformer? Gary

Author:  garydounson [ Tue Aug 25, 2020 11:43 am ]
Post subject:  Re: Labeling of MV Pad Mount Distribution Transformers

Hello Mike, I seem to have deleted the link you provided to the website in you post. Could you please post it again. Thanks

Gary

Author:  mpparent [ Tue Aug 25, 2020 2:11 pm ]
Post subject:  Re: Labeling of MV Pad Mount Distribution Transformers

Article by e-Hazard:
I don't like the idea of multiple labels...but may be necessary in some instances. I don't think there is an industry standard, so you get to decide the route you want to go.

Mike

Author:  wbd [ Thu Aug 27, 2020 6:37 am ]
Post subject:  Re: Labeling of MV Pad Mount Distribution Transformers

If this padmount is owned by the utility, then there should be no labels on it as it falls under OSHA 1910.269 and in the forward, OSHA discusses that it does not believe that providing labels on transmission and distribution installations is feasible or effective. Even if the padmount is customer owned, it probably falls under OSHA 1910.269 because of utility like voltages and equipment.

Since the NESC is referenced, I would think this installation is under OSHA 1910.269 for arc flash

Author:  garydounson [ Thu Aug 27, 2020 3:57 pm ]
Post subject:  Re: Labeling of MV Pad Mount Distribution Transformers

Thank you Barry and Mike. Excellent feedback and information. Gary

Author:  Reeberas [ Wed Sep 02, 2020 5:31 am ]
Post subject:  Re: Labeling of MV Pad Mount Distribution Transformers

If it was a substation transformer with side bushings and enclosures would you label the two enclosures differently?

Author:  wbd [ Wed Sep 02, 2020 6:13 am ]
Post subject:  Re: Labeling of MV Pad Mount Distribution Transformers

See above response regarding OSHA labeling for utilities.

Author:  Highkvs [ Mon Oct 05, 2020 8:52 am ]
Post subject:  Re: Labeling of MV Pad Mount Distribution Transformers

The sign should read:

Danger
Do Not Touch
Not Only Will This Kill You
It Will Hurt The Whole Time

Page 1 of 1 All times are UTC - 7 hours
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group
http://www.phpbb.com/