Originally Posted By: kmcmahon This post was automatically imported from our archived forum.
The owner of the home was behind me when I saw this in the panel.
Apparently, the flooring contractors could not locate a 220 outlet for their powersander, so decided to hardwire their extension cord to the main service conductors and accidentally crossed the wires causing an arc flash!  Unreal!
Originally Posted By: bbadger This post was automatically imported from our archived forum.
Hi Kevin.
Unfortunately many of the folks who sand floors are seriously uneducated of the dangers of doing what you describe.
It is very common to see these guys with cords that have large 'alligator clips' to clip onto what ever they can find in the panel.
They may clamp right to the bus which at least will be somewhat protected by the main or they may clip on the line side of the main breaker with no protection from full utility current.
This is often done with 10 or 8 AWG cord, beside the danger of actually making the live connection if the cord or motor shorts out it will likely vaporize the entire cord in one large flash. At this point the condition of the floor will be the least of the homeowners problems.
Just to make things more dangerous they are likely not to connect the grounding conductor.
Bob
-- Bob Badger
Electrical Construction & Maintenance
Moderator at ECN
Originally Posted By: kwilliams This post was automatically imported from our archived forum.
bbadger wrote:
Hi Kevin.
they may clip on the line side of the main breaker with no protection from full utility current.
Just to make things more dangerous they are likely not to connect the grounding conductor.
Bob
Bob, yep, your right on, had this happen on my own house 2 years ago.
when I came home from work the sander was about half done.
when I said what the hell are you doing, he said " do it all the time "
He didn't finish the job ......