"Phab E. Oh" wrote:
I'm in Japan and having a problem with a US
monitor.
It won't turn on...no power light or power up noises
or anything.
So I measured voltage across neutral and ground and
there was 8VAC. So I got an electrician to wire up a
proper ground. There's still 1VAC across Neutral and
Ground.
So I have two theories:
1) The monitor is seeing the floating ground and not
liking it and refusing to turn on.
2) The monitor requires at least 110V (I'm getting
103V).
I'd hate to think this thing just died, so can anyone
confirm that a ground to neutral measurement should
yield 0V or some very negligible voltage?
If you are measuring between GND and neutral, a few volts measured is not surprising
(especially with a DMM with a high input impedance), resulting from inductive/capacitive
coupling between wires over the distance between your measurement point and where GND and
neutral are bonded in the building (assuming that Japan does a straight GND/neutral bond
as is done in North America).
The 103V supply voltage is far more suspicious, as it is quite low relative to 115V (you
don't say how old the monitor is, could it be that it predates power supplies with
'universal' supply voltage range?). Try finding a power adapter transformer to
boost the voltage. (Normal Japanese line voltage is lower than North America isn't
it?). Or if you are around electronics people, try to find a variac, as variacs typically
have some boost on the upper end of their range (for example, a variac fed with 120V will
typically boost to at least 130V, keeping in mind if the variac scale is presented in
volts, the scale accuracy will vary with the input voltage). (Or, being very careful not
to go to the low end, wire up the variac in reverse).
Or (if the monitor is older) there's always looking inside the monitor for jumpers, or
alternative primary taps on a power transformer, to select input voltages.