On 6/26/2015 6:44 AM, Richard Owlett wrote: > Fred James wrote: >> Jim Garrison wrote: >>> LCD monitors are not subject to magnetic interference the way >>> CRTs were, so making a Faraday cage out of aluminum foil will not >>> work. The fan is causing your power to fluctuate. It shouldn't >>> be doing that, and if it does there may be a problem with the >>> building's wiring. You should notify your building management >>> and ask them to get an electrician to come out and diagnose the >>> problem with the fan. There's a *small* chance this could be a >>> fire hazard in the fan. >>> >> Jim Garrison This is an interesting thought, and interesting >> information. One more question ... there are two monitors in this >> room, about 6-7 feet apart. The one near the outside wall is the >> one that "flickers" and goes black. The one 6-7 feet further in >> seems not to be effected at all. Both Monitors are on UPS (separate >> UPS for each system), and both UPS are plugged into the same wall >> socket. Does that information effect your thoughts on this issue >> in any way? Thank you Regards Fred James
Physically swap the monitors (i.e. move them) and see what happens. If the same monitor continues to have a problem then that monitor is overly sensitive to voltage transients. If the problem stays near the outside wall, then it's likely the UPS that has the problem. For step 2, leave the monitors swapped and physically swap the UPSes. That should confirm where the problem is. > Additional note ... the UPS supporting the blinking monitor also > supports the desktop machine, and two network devices ... only the > monitor (as far as I can tell) is suffering. The desktop machine has a power supply that is designed to cope with wide input fluctuations of the type caused by other loads on the input power line. It isolates your computer quite effectively. The network devices may just not be very sensitive, or their wall-warts do a reasonable job. Note that typical consumer UPSes do not isolate downstream equipment from voltage fluctuations that do not also trigger a switchover to battery power. I.e. it's not a power conditioner. Based on your comments I think it's more likely that either the monitor or UPS is the problem, with the monitor's power sensitivity the most probable cause. -- Jim Garrison ([email protected]) PGP Keys at http://www.jhmg.net RSA 0x04B73B7F DH 0x70738D88 _______________________________________________ PLUG mailing list [email protected] http://lists.pdxlinux.org/mailman/listinfo/plug
