ENERGIZED WORK

[bure961]

Should the company have the contractor inform them when the contractor is at the point of tying his wires to the starter, breakers ?,,,
Contractors have always said we are carefull we use pvc poles or snakes when pulling wire into a conduit that has other energized wires in the conduits . Should the wires in the conduits be deenergized before any wiring is pulled regardless of the type of snake being used ?

 

[Smart $]

I realize there are exceptions to the "rules", but how hard is it to understand that you must have a very, very, extremely very good reason to perform energized work. Then there a simple matter of logic involved with pulling new wires in the conduit with other wires that are energized. What is the probability the enclosures at each end of the pull are energized???

There ought to be a rule on this forum that you must substantiate any reason for doing energized work before asking questions related thereto...

 

[petersonra]

You might be able to find a safe way to do some of this stuff. If so, I don't have a problem with doing that.

The problem is that what some people consider "safe" often isn't.

 

[RichB]

That's a good question--and it gets me thinking--if I am adding breaker to a panel in the house--do I need to shut off the main just to snap a breaker into place--or if I am terminating to and existing breaker do I need to kill the whole panel as the breaker itself is open--I think by letter of law the answer is yes--de-energize it but how many of us really do or have thought of that

 

[gadfly56]

That's a good question--and it gets me thinking--if I am adding breaker to a panel in the house--do I need to shut off the main just to snap a breaker into place--or if I am terminating to and existing breaker do I need to kill the whole panel as the breaker itself is open--I think by letter of law the answer is yes--de-energize it but how many of us really do or have thought of that

On the few occasions I have added a breaker to my home panel, I have always killed the main. I remember one time working on a loose switch in my parents' house several decades ago. Touched hot and the box with one of my DMM lead probes. It left a big impression (and notch in the probe), and I decided that working hot wasn't for me from then on.

 

[Timbert]

As stated, there are rare exceptions to working on de-energized equipment. Convenience and loss of production aren't in the list of exceptions. Neither is "we can do it safely some other way" or "I've done it a thousand times and nothing happened."

NFPA 70E lists three general exceptions.

1. Greater hazard
2. Infeasibility
3. Less than 50 volts

So, if you're troubleshooting life support equipment running on 24 volts you're golden. If we take RichB's example, no additional hazard would be created by shutting off the mains, it's certainly feasible, and the circuit is more than 50 volts, so why isn't everyone turning off (and locking out) the mains?

 

[RichB]

On the few occasions I have added a breaker to my home panel, I have always killed the main. I remember one time working on a loose switch in my parents' house several decades ago. Touched hot and the box with one of my DMM lead probes. It left a big impression (and notch in the probe), and I decided that working hot wasn't for me from then on.

Been there done that!!!hmy: My wife comes and starts talking to me when I am changing out a switch or a recept--asks me if that is hot and if I pull back she knows it is--well she just keeps on talking and asking questions till I go turn it off--got me trained now--I de-energize automatically--except in the panel--never thought about it--gonna have to start tho-I like my grandkids and intend to hang around and make life miserable for their parents!!!:ashamed::rotflmao::angel:

 

[gadfly56]

Been there done that!!!hmy: My wife comes and starts talking to me when I am changing out a switch or a recept--asks me if that is hot and if I pull back she knows it is--well she just keeps on talking and asking questions till I go turn it off--got me trained now--I de-energize automatically--except in the panel--never thought about it--gonna have to start tho-I like my grandkids and intend to hang around and make life miserable for their parents!!!:ashamed::rotflmao::angel:

Yeah, we've started up recently trying to get a handle on 70E since our sprinkler techs have to take current measurements on 480 fire pumps, which means working inside a hot cabinet. I think we now have a 40cal suit in the tool crib. It's only recently that I've started to wonder what the arc flash potential might be in a typical 200 amp home panel. Think I'll stick to not trying to find out. hmy:

 

[Fulthrotl]

Should the company have the contractor inform them when the contractor is at the point of tying his wires to the starter, breakers ?,,,
Contractors have always said we are carefull we use pvc poles or snakes when pulling wire into a conduit that has other energized wires in the conduits . Should the wires in the conduits be deenergized before any wiring is pulled regardless of the type of snake being used ?

yeah. even if you are using a plastic snake, this means you are most likely in a live panel at one end,
and a hot junction box at the other end.

as others have mentioned, NFPA 70e is the guiding policy here.

and the one, if someone gets hurt, that you will be hung with.
you were in a hot panel doing work 'cause it was inconvenient
to shut down the panel.

you have no defense at all. zip.