Philips Monitor

[Tim_axe]

You wouldn't happen to have large and powerful AC units along with refrigrators on that same circuit would you?

A condition known as "dirty power" can possibly cause the effects you mentioned. This is where the AC sine-wave gets heavily skewed from strong non-linear loads. If you have a power-conditioning active UPS you should plug the monitor into it and see if it solves the problem. Or take the monitor home and try it out there. If it cleans up and stops shaking, chances are it is an issue with this dirty power stuff. Some monitors are more susceptable to it than others, usually depends on how powerful their PSU is and the size of it's capacitors, etc.

Anyways, hopefully your next monitor deals with whatever the issue is better than this one.

[foxyloxley]

Following on from Tim_axe:

Computers and their peripherals should be on a 'clean' circuit.
That is, a circuit solely for them. Plus, the earth continuity conductor [ECC] should also be a 'clean' varient, in that it should travel back to where the power enters the building, and preferably, it should go right back to the incoming transformers.

This is because the PC is a delicate beast, and in an industrial setting, with a lot of inductive loads [AC motors, fluorescent lighting etc] then the AC can get a little out of whack.

Initially the [V] volts and [I] amps are in phase ( or close as make no difference ) after an inductive load, the amps begin to 'lag' the volts. This leads to a situation wherein the sine wave will effectively have two peaks, one for V, and one for I. To combat this, capacitor banks are fitted (their size requirements are calculated with regard to the area load v inductive load)
Capacitive loads have the opposite effect to inductive, in that the volts lag the amps.

If the calcs are correct, then the site would be in balance. Another reason to do this is if you have your 'two' peaks hitting the meters, you pay for each hit ...............
That is, you are paying extra money for something that you never got.

As for the 'clean' earth, this is because electricity is basically lazy. If there is an electrical short to earth, anywhere on the system, the fuse will blow. But, before it blows, the entire ECC system will raise its potential to the same as the mains voltage, and it will all flow to the nearest earth point. This is a safety feature to prevent you touching a high potential piece of metal, and a low potential piece of metal at the same time. As ALL exposed metalwork will be at the same potential.

If the system is ABCDEFGH, and the PC's are in section D, and you get a short in any of the other sectors, then the entire system will liven up. This means that fault current will travel through the PC area, with all their attendant spikes, causing mayhem in their passing.

In a clean earth situation, the ECC from sector D will go direct to the start of the system - A.
Now if a short occurs anywhere, the clean earth is NOT bonded to earth at the PC's it is only bonded at the incoming end, this means that the electrical fault current cannot flow up to the PC's as there is no path. Fault currents can only flow OUT.............

Get an Elec/Tech with an oscillascope[sp] to test the AC in your area, you SHOULD have a nice smooooth sine wave, with little or no spikes. [spikes = noise = nastiness] Check it whilst normal running conditions prevail, then check with everything OFF.

Confirm that you have a clean earth. One that runs from the PC's direct to the incoming point for the buildings AC power. And is only bonded at the incoming end, it should be a 'floating' earth at your end.

A 'dirty' power supply will kill systems just as quick as it will kill you.

[edit] A quick fix is to use a VDR [voltage dependant resistor] in your monitor plug top, across the line and neutral. This will act like an 'overflow' or a Zener diode, in that if the volts stays constant, then the VDR will allow all to pass through, if there is a spike in the line, the VDR will allow only what its rated for, and the rest will be allowed to pass across the VDR to the neutral pin.[/edit]

[CybertecOne]

thanks foxyloxey and yea, im pretty uptodate on electronics

thanks guys, will keep an eye out on whats going on.. yes, the monitor is and has been plugged into the ups with supports the monitor and computer only... and still same effects etc etc...

i'll let you know what happens if anything does