Ian Malcolm wrote:

Steve Smith wrote:


Jon Elson wrote:



Ignoramus18851 wrote:

On Thu, 12 Jan 2006 13:37:45 -0800, Glenn wrote:


Don't overlook the incoming power feed.



Yes, I will definitely check that. My incoming power lines are
connected to the electrical panel with Allen style set screws. They
are before the main breaker, so, I will have to be very careful
tightening them, as they cannot be turned off.

Those things scare the HELL out of me, and I work on live 240 V gear
all the time. I can't think of ANY safe way of tightening those, without
making a special tool. If that L-shaped allen wrench touches anything
else,
like the electrical box, the explosion will be totally awesome, and you
don't want to be anywhere near it. If you are not familiar with the term
"arc flash" you might want to read up on it. A 240 V residental service
doesn't really supply the watts that can get into serious arc flash
territory,
but it could still send you to the hospital.

I'd avoid using an L shaped allen wrench. I used a straight ball driver
with a large insulated handle on it.

Steve

I *HATE* and *DETEST* working live.

I cannot reccomend that you do so, but hypothetically, - if you were to
consider doing it yourself - further to the other peoples comments, take
off metal rings, watch straps, neck chains etc. Dont wear *any*
synthetic fibre clothes that can melt or burn etc. Outer clothing
should be heavy wool or leather (cotton burns too easily) and cover as
much of your skin as possible. Wear goggles or protective glasses,
vaporised copper goes a surprising distance and wont do your eyes any
favors. Gumboots would be a good idea in addition to the DRY insulator
to stand on. To reduce the risk of taking a shock across the heart, keep
one hand, preferably your left in your pocket at all times. Have a
trained first aider standing by with a phone, a dry powder fire
extinguisher, a blanket to put you out if you are the fire and a dry
broomstick to seperate you from the line just in case. Remember, if you
are working live, any earthed surface or object is a hazard. You cant
shield the terminals you need to tighten but you may be able to shield
most of the box, conduits etc. so there is NO WAY you can come into
contact. Remove or protect any sharp objects etc. you could get thrown
against. Make *SURE* you have good enough lighting, and that it is NOT
dependent on the circuit you are working on. Dont have a hangover,
coffee, too much tea, be tired or just awakened or unwell - you need a
steady hand and a clear head.

Final advice, *HIRE IT DONE*

--
Ian Malcolm. London, ENGLAND. (NEWSGROUP REPLY PREFERRED)
ianm[at]the[dash]malcolms[dot]freeserve[dot]co[dot]uk [at]=@, [dash]=- &
[dot]=.
*Warning* SPAM TRAP set in header, Use email address in sig. if you must.

I think your going a bit overboard there, those precautions are a bit
more suitable for primary work or at lease 480V switch gear. Remember
that we are talking about 120V here, it doesn't take that much to
insulate against 120V, heck where you are you use 240V as your normal
household voltage. The threat in what's being proposed comes from the
high currents available, not from the voltage.

Bolt-on type circuit breakers are routinely connected live and not much
of a problem. The key thing is that there is generally a main breaker
upstream to shut things down in the event of a short. Working live
before the main breaker if there is a short things will stay lit up
until something melts open, doing a lot more damage.

Pete C.