|
Posted by J. Clarke on June 18, 2006, 8:20 pm
Pete C. wrote:
> "J. Clarke" wrote:
>>
>> Pete C. wrote:
>>
>> > "J. Clarke" wrote:
>> >>
>> >> Pete C. wrote:
>> >>
>> >> > "J. Clarke" wrote:
>> >> >>
>> >> >> Pete C. wrote:
>> >> >>
>> >> >> > "J. Clarke" wrote:
>> >> >> >>
>> >> >> >> Pete C. wrote:
>> >> >> >>
>> >> >> >
>> >> >> > <snipped>
>> >> >> >
>> >> >> >> > Have to agree. The normal snap in breakers are very much
>> >> >> >> > comparable to a regular 5-15 plug connection.
>> >> >> >> >
>> >> >> >> > You are holding an insulated breaker case equivalent to an
>> >> >> >> > insulated plug, and you are connecting / disconnecting a
>> >> >> >> > spring pressure connection just like a plug.
>> >> >> >> >
>> >> >> >> > All is at the same voltages you get with normal plugs, even
>> >> >> >> > with a two pole breaker since 6-20 and 6-30 and 6-50 plugs are
>> >> >> >> > common household items as well.
>> >> >> >>
>> >> >> >> With "normal plugs" you don't have an exposed 240 volt bus on a
>> >> >> >> 100+ amp breaker.
>> >> >> >
>> >> >> > With a quality panel (like a Square D QO) you don't have a lot
>> >> >> > that's exposed either. It's also still only 120V to ground so
>> >> >> > unless you stick both hands in and touch both legs the 240V part
>> >> >> > is rather irrelevant.
>> >> >>
>> >> >> With the cover off the entire bus except those parts covered by
>> >> >> breakers is exposed, and it's a lot easier to get your hand across
>> >> >> two lugs than it is to get it across one leg and ground, so you're
>> >> >> more likely to get 240 than 120.
>> >> >
>> >> > First off you should take a closer look at the QO panels, they have
>> >> > a "shielded bus" design that only exposes the actual breaker
>> >> > connection points, the rest of the busses are shielded unlike most
>> >> > other brands.
>> >>
>> >> So? Juice is juice. The "actual breaker connection points" are quite
>> >> sufficient.
>> >
>> > Sufficient yes, but it's about 10% of the exposed live bus of most
>> > other brands so there is significantly less area to potentially
>> > contact.
>> >
>> >>
>> >> > Second point is that 240V across your fingers may not be nice, but
>> >> > it's still only 120V through your body to ground and that's what
>> >> > counts.
>> >>
>> >> Are you really this ignorant?
>> >
>> > Apparently you are.
>> >
>> >>
>> >> > Whether you get a lethal current across your heart depends on a lot
>> >> > of factors, but your fingers contacting a single 120V terminal or
>> >> > bridging across for 240V isn't one of them.
>> >>
>> >> Depends on which fingers. One finger, no, one on each hand yes.
>> >
>> > If you're dumb enough to manage to get one hand on one bus and the
>> > other hand on the other bus we don't need you in the gene pool.
>> >
>> >> >
>> >> >>
>> >> >> >> > If you feel better turning off the main then by all means do
>> >> >> >> > so, it's only your time to reset everything that you're
>> >> >> >> > wasting, but don't insist that everyone else should do the
>> >> >> >> > same.
>> >> >> >>
>> >> >> >> If you want to risk your own life to save resetting a couple of
>> >> >> >> clocks
>> >> >> >> that's your choice. But to advocate that to a complete stranger
>> >> >> >> who admits to being clueless with regard to electrical wiring is
>> >> >> >> irresponsible in the extreme.
>> >> >> >
>> >> >> > I never advocated that the OP do anything, I corrected someone's
>> >> >> > incorrect assertion that most people turn the main breaker off to
>> >> >> > change a branch circuit breaker. The fact is that most people do
>> >> >> > not turn the main breaker off to change a branch circuit breaker
>> >> >> > and in a couple decades of misc. electrical work I've not run
>> >> >> > across a single person that did.
>> >> >>
>> >> >> You are asserting that this is a _fact_. I should like to see the
>> >> >> methodology by which you determined this. And don't say "everybody
>> >> >> I know" does it unless you are prepared to demonstrate that
>> >> >> "everybody you know" is a random and representative sample of the
>> >> >> population.
>> >> >
>> >> > I consider the fact that I have not seen a single person do it in
>> >> > 20+ years and hundreds of electrical projects with dozens of people
>> >> > a sufficiently representative sample to conclude that most people do
>> >> > not turn off the main. It would be a stretch to conclude that nobody
>> >> > did, but it's a reasonable assessment that most do not.
>> >>
>> >> I would say that rather than telling us what most people do, you are
>> >> telling us that you _really_ need to find some smarter friends.
>> >
>> > Nope, at least 75% of those people were professionals and good ones at
>> > that who primarily do commercial work, not the hacks that only do
>> > residential because they aren't good enough for commercial.
>>
>> If you are located in CT or MA I want a list of these people so I know
>> who
>> to avoid in the future. Otherwise, I'm looking forward to your Darwin
>> Award.
>>
>> --
>> --John
>> to email, dial "usenet" and validate
>> (was jclarke at eye bee em dot net)
>
> Suggest you call around and as any licensed electrician if they turn off
> the main breaker when replacing a branch circuit breaker (unless the
> breaker being removed is physically damaged of course). Suspect you
> won't get a single affirmative answer.
>
> Do you also turn off the main breaker when changing a light bulb?
Not an analogous situation in _any_ sense.
--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)
| 
Yahoo! 
Google 
Windows Live 
del.icio.us 
digg 
Netscape 
XML Sitemap