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Re: OT: Computer's electrical outlet



Frank Cox wrote:
> 
> Electrical regulations vary substantially from place to place even within the
> same area. I have electrical inspectors (gas inspectors, fire inspectors,
> health inspectors, boiler inspectors, inspector inspectors I suppose) go
> through my theatre on a regular basis.  One of those guys told me that it's
> illegal to use an extension cord in commercial building in some cities around
> here.  Not in my city, though -- I had never heard of a restriction like that
> before.
> 
For a lot of places, this is a fire regulation violation, and not an
electrical code violation. There are a couple of problems with using
extension cords. One of the biggest is that it is too easy to damage
one if you do not have it routed properly. Another problem is that
too many people use a cord that is too light for the job. Extension
cords come in different gages. There is often a chart showing what
gage cord is needed for what type of load, and what distance. And
you can really run into problems when you string then together. For
example, if you have 2 16 gage, 100' cords strung together, you can
short out the cord, and not trip a 20 amp breaker. The resistance of
the wire is enough to limit the current. It works well when you need
to free up a cord frozen in the snow. You can sometimes do it with a
pair of 50' cords as well.

You also run into problems whey you start connecting motor loads.
Something like a small refrigerator or dehumidifier can cause real
problems. They may work fine under  normal usage, but the first time
the power is interrupted when they are running, and then comes back
before the head pressure has bled off, you will have problem. The
motor can not get enough power to start under load, or to trip the
breaker, so it sits there, drawing the maximum power the cord will
provide, all the while the cord is acting as an electric heater
until it burns up, possible starting the building on fire.

Also, the ban may not be on all extension cords. It may allow
appliance extension cords. These are normally 12 or 14 gage wire,
and are fairly short. This means they can carry enough current, and
are less likely to be subject to physical damage.

Oh yes, cords are not allowed to be run through walls, ceilings or
floors. They are not allowed to be run in ceilings, nor where
subject to physical damage. This one reason that you see the metal
peace covering cords that have to cross a traffic area. (walkway)
The other is to prevent people from tripping on them.

Mikkel
-- 

  Do not meddle in the affairs of dragons,
for thou art crunchy and taste good with Ketchup!

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