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That is a 'bolted' fault with no overcurrent protection.

Working in a live 480 panel is nothing new. OSHA does not allow anything to be worked on live, but who is honestly going to shut down a building just to add a few lights?

The union does not allow anyone to work near 480 alone, the person has to be accompanied by a coworker that knows CPR(which every union electrician knows CPR)
 

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That is a 'bolted' fault with no overcurrent protection.

Working in a live 480 panel is nothing new. OSHA does not allow anything to be worked on live, but who is honestly going to shut down a building just to add a few lights?

The union does not allow anyone to work near 480 alone, the person has to be accompanied by a coworker that knows CPR(which every union electrician knows CPR)
So CPR does what for the burning sensation caused by the extreme heat of the blown up metal? So you get to live but you look like fire marshall bill, great.
 

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I worked at a large sawmill in my teens and twentys. There was a huge conveyor that would get hung up once in a while. The operators would call for an electrician to swap phases and reverse the chain to get it unstuck. This would happen once in a while. After one operator saw me (on a few occasions) turn off breaker, reverse two wires on the top of the starter, and back chain up. He decided he was going to do this himself rather than call maintenance. He turned off the breaker, and removed the wires OUT OF THE TOP of the breaker. While swapping them, he touched them together, BOOM!!! 480 volt phase to phase short. The wire was a tap in a 3000 amp MCC. It burned him pretty bad.
 

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I worked at a large sawmill in my teens and twentys. There was a huge conveyor that would get hung up once in a while. The operators would call for an electrician to swap phases and reverse the chain to get it unstuck. This would happen once in a while. After one operator saw me (on a few occasions) turn off breaker, reverse two wires on the top of the starter, and back chain up. He decided he was going to do this himself rather than call maintenance. He turned off the breaker, and removed the wires OUT OF THE TOP of the breaker. While swapping them, he touched them together, BOOM!!! 480 volt phase to phase short. The wire was a tap in a 3000 amp MCC. It burned him pretty bad.
Wow! They (operators) always seem to think some of the stuff we do is so simple.

Nice post:thumbsup:
 

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That is a 'bolted' fault with no overcurrent protection.
No, that is not a bolted fault, the is no arc on a bolted fault. That is an arcing fault, created by PSE&G by bridging a 10mm gao witha fine copper wire to initiate the fault current of arounf 30kA, the OCPD cleared the fault in 30 cycles or so, as designed. This is a common test set up and I have witnesed it my self at Kema labs.

Working in a live 480 panel is nothing new. OSHA does not allow anything to be worked on live, but who is honestly going to shut down a building just to add a few lights?
People that follow OSHA laws and 70E work practices, people that are employed by companies that claim they are 70E compliant, and people who are not stupid and hate burn units.

The union does not allow anyone to work near 480 alone, the person has to be accompanied by a coworker that knows CPR(which every union electrician knows CPR)
How will CPR help anyone following an arc flash accident?
 

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The union does not allow anyone to work near 480 alone, the person has to be accompanied by a coworker that knows CPR(which every union electrician knows CPR)
That's another load of crap. The only time I have ever been taught CPR is when I took the voluntary OSHA 30 course. The local does not teach CPR, nor does it require the members to learn it.
 

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No, that is not a bolted fault, the is no arc on a bolted fault. That is an arcing fault,
i have seen this video before and view it as one of the things that make me want to be a safe person with this potential of harm

zog is their no arc flash with a bolted fault? why is that? remember you are talking to someone that has only been self educated in arc flash saftey
 
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