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Re: gfci

Kinney, Travis said, in part:
> Not sure why you want to install a GFI as most power strips have a
> surge
> protector fuse in them. If were to drop your hairdryer into your fish
> tank,
> the surge would 'pop' the fuse in the power strip (if it has one).

Most surge protectors are pretty useless even for their intended
purpose but certainly as protection against electrical hazards
resulting from ground fault conditions.  Surge protectors will protect
against momentary spikes, sometimes relying on capacitors as frequncy
filters.  Sometimes using temperature sensitive resistor elements.  The
reduce instaneous voltage peaks.  If the peaks last for more than an
instant, many so-called surge protectors burn through and cease
providing surge protection but continue to pass current.  Some have
fuses in them, but the amount of current that can injure or kill a
human can be much lower than what it takes to melt a fuse.  Even if it
doesn't kill you or burn you, a seriious jolt from 110 volts is not
pleasant, to say the least.

GFCI and ground fault protectors are intended to prevent electrical
hazards and reduce the possibility of shock by breaking a circuit when
the amount of current flowing through the "hot" power supply wire is
different than the current flowing through the "neutral" power supply
wire -- the assumption in the design here is that if the flow is
different, then some must be leaking to ground somewhere, hence the
term ground fault.  In fact, because of this design, GFCIs will work
even on two-wire circuits that have no ground wire.

> GFI's are
> great, but if the circuit has a lot of other outlets or lights on it,
> you
> may find it kicking off a lot!

Generally, this only happens if the other devices are behaving badly,
leaking too much RFI, feeding back too much harmonic distortion into
the house wiring.  Such stuff is out there, but I have never come
across one.  If you find this problem, it would be wiser to seek out
the naughty device rather than give up the safety provided by the GFCI.

> They are easy to install. Just shut the power off to the existing
> outlet and
> then wire it in.

Oh not quite so.  They (or many of them) can be wired in several
different ways so that the GFCI protects only items plug into it, all
sockets on the same circuit, or only some sockets on the same circuit. 
This might seem a small point to some, and it doesn't make the job
terribly difficult *but* you have to be comfortable reading and
understanding the wiring diagrams, understand the warnings about
aluminum wire (if that's what you have), and all the other alerts
provided with the device.  A GFCI is not like a PC lamp that might not
light up if hook up the wires incorrectly -- there is terribly more at

Scott H.

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