Normally energized MV Worker Protection

[Zifkwong]

Can someone tell me what standards or regulations apply to the industrial environment regarding how to protect workers when working on a piece of equipment? I came from the utility and now I work at an industrial plant. The utility had procedures that dictated if you were to work on a piece of MV equipment you had to have a break from any source of potential and the equipment must be grounded. Is there any regulations or standards that say something similar or provide guidance on work practices? NFPA 70E?

 

[ramsy]

You'll find some qualified opinions that discuss medium voltage here in the recent past. Searching all Mike Holt's forums for the phrase "chicken switch" should get some of those discussions. Otherwise, short of getting an actual copy of NFPA 70E, a current thread with Medium Voltage link to OSHA is here; http://www.mikeholt.com/codeForum/viewtopic.php?p=1182243#1182243
There are also some related NFPA articles currently linked here. http://www.mikeholt.com/codeForum/viewtopic.php?p=1182421#1182421

 

[zog]

Ground it

Ground it

Well the isolation is obvious. The grounding is not so clear. The 70E discusses applying grounds if the is a possibility of stored energy or induced voltages or if it can be reasonable anticipated the conductors could contact other live conducters (Etc.)

Now if your feed is a MV cable, they may store a charge, our policy is ground anything >600V.

 

[realolman]

I don't remember any regulation numbers, but I know you are required to maintain a book(s) that contains everthing in the plant, identifying all the energy sources, and how to render it energy "neutral"., disabling obvious stuff like electricity, but also things like counter weighted machine members that could comprise stored kinetic energy.
I'm sure what you're talking about would be included in it.


I think it's OSHA.
Hazardous energy something or other.
Memory is the second thing to go.

 

[ramsy]

Just posted some good info here: http://www.mikeholt.com/codeForum/viewtopic.php?p=1182959#1182959