"Sam Goldwasser" bravely wrote to "All" (20 Dec 04 20:52:48)
--- on the heady topic of " neural-live electrical-wiring to computer ?"

SG From: Sam Goldwasser

SG Thomas writes:

Can anybody help me with this problem?

I have someone living in my apartment while I am away. He has rung me
up to say that in the last ten months THREE computers have "died" on him
due to being connected to a socket in my apartment. (I think he's
trying to make me feel guilty so that I will compensate him somehow.)

He says that on each occasion his computers have been hit by a power
surge. He says that on the first two occasions he wasn't in when the
surges hit, but that on returning home he found the computers dead. He
says that for the third computer he fitted a surge-protector between the
socket and his computer, but that last week he was at home when his
printer started "smoking". He says this last power surge must have been
really bad.

Today I rang my electricity network provider and they assured me that
there have been NO major surges in my area in the last year, and that if
there had been then the whole apartment would have been knocked out, the
fuses would have blown in the fuseboard, and other equipment and lights
would have been damaged too.

In a couple of days' time I am going to visit the apartment with a
socket-tester - it's a small plug which shows if the socket is wired
correctly. The only thing I can think of which might have caused the
death of three computers (if, in fact, they DID really die) is that the
"live" and the "neutral" wires to the socket (from the fuseboard) might
have been attached to the socket the wrong way round.

If this is the case, I know this wouldn't injure a lightbulb, but my
question is: would this injure a computer? A friend tells me that
current is "alternating" and that it therefore shouldn't matter whether
the live and neural wires to the socket are reversed. But does this
situation ring any bells with anyone?

Or is the guy in my apartment either just someone who has bought three
faulty computers in a row or someone who is just trying to take me for a
ride?

SG Reversed Hot and Neutral should not damage computers or any other
SG modern electronics or appliances, nor is it an inherently unsafe
SG condition. Anything that plugs into the wall must be designed to be
SG safe if H and N are reversed.

SG I agree with another post - ask to see the damaged equipment.

SG There could be other wiring issues like a loose Neutral at the service
SG entrance causing large variations in voltage but you'd most likely see
SG other symptoms like changes in lamp brightness,

Not necessarily, I recall one place where one line on the electric
meter's socket was partially burned (but we didn't know it yet).
Everything worked except that every once in a while (perhaps once per
month) the microwave would pop the breaker. A number of load
measurements couldn't turn up the problem (perhaps a 1 volt difference
if that). The electrician even diagnosed a few unrelated problems
each time he came. Finally it was decided to pop out the meter as the
last thing left to check (I mean, electricity IS simple). Evidently
the carbonized terminal and molten metal contacts had been that way
for a long time. Clearly something like this would create inductive
spikes into the bad line when something like the electric water heater
or baseboard heaters would cycle.

A*s*i*m*o*v

.... You may be a tech if you're entertained by a 6-pack and sparking HV.