Need help with monitor in Japan

From: Paul Koning <pkoning_at_equallogic.com>
Date: Wed Jul 14 08:21:32 2004

>>>>> "Phab" == Phab E Oh <phabi0_at_yahoo.com> writes:

 Phab> Hi All. I'm in Japan and having a problem with a US
 Phab> monitor. It won't turn on...no power light or power up noises
 Phab> or anything.

 Phab> So I measured voltage across neutral and ground and there was
 Phab> 8VAC. So I got an electrician to wire up a proper ground.
 Phab> There's still 1VAC across Neutral and Ground.

Shoddy wiring... not quite as shoddy now, but still pretty bad.

 Phab> So I have two theories:

 Phab> 1) The monitor is seeing the floating ground and not liking it
 Phab> and refusing to turn on. 2) The monitor requires at least 110V
 Phab> (I'm getting 103V).

 Phab> I'd hate to think this thing just died, so can anyone confirm
 Phab> that a ground to neutral measurement should yield 0V or some
 Phab> very negligible voltage?

You can test that by wiring up a temporary adapter that connects
ground and neutral together. Do NOT use that for normal operation
because that would be dangerous.

I doubt that's the cause, though. The low voltage may be the reason.
But competent designers know that Japan's nominal AC voltage is lower
than the USA -- so the standard test spec for power supplies is 95 to
265 volts (low end of Japan to high end of UK).

If you can get your hands on a Variac that has the winding extending
beyond the input, you can boost the voltage to the monitor.

You might try a different location. It may be that you're suffering
from really bad wiring with unusually large voltage drop.

 Phab> Assuming the above two theories are bunk...any other ideas?

Your monitor may be busted... :-(

     paul
Received on Wed Jul 14 2004 - 08:21:32 BST