IMHO, you are not being paranoid
I have an old Zeiss 200-watt ("pumpkin lamp) system, and I wish I knew how
far away was far enough. I once fried a board in the zeiss MC100 camera
attached to my Universal when I started the lamp (the camera was turned
on, and its controller sits right next to the microscope). On another
occasion, I took out the power supply in a Macintosh connected to a
different microscope in the room (the computer was on) and burned a short
trace on the screen of a video monitor that was a good 8 feet away (the
monitor was on). All of this became somewhat more understandable when,
after I hooked up a stereo in the room (some 12 feet from the fluorescence
'scope), I noticed a loud "POP" from the speakers whenever I pressed the
igniter button on the lamp supply. There are two other computers in the
room, some 25 feet from the lamp. They have never been affected.
So I would guess that the EMP originates from the lamp and the cord, and
that having the equipment on different circuits, or having
surge-protectors on the circuits offers no protection whatsoever. I now
make sure that *everything* within a fifteen-foot radius of the lamp is
turned off before I start the lamp.
Julian Smith III
> I have some questions concerning the prudent use of UV (e.g.
> mercury/xenon lamp) power supplies. We are setting up a new microscope
> that is equipped with an Opti-Quip Model 1600 Power Supply powering a
> 200 watt mercury/xenon lamp. I'm concerned about warnings I've read
> about turning off all other electrical equipment before firing up the
> lamp (because of a strong electromagnetic pulse induced when the lamp
> ignites). We plan to follow this advice and turn off all the
> electronics in the immediate vicinity of the power supply , but how far
> (literally) do we have to go in shutting down electronics in the room.
> For instance, must we turn off a computer monitor that is ~8 feet or a
> computer that is ~12 feet away from the Opti-Quip--what is a safe
> distance? Does it matter whether or not the electronics are on the same
> power circuit as the power supply? Does the EMP originate from the
> power supply or the lamp? What other precautions should we be taking?
> (or am I being paranoid?). Thanks in advance for whatever advice anyone
> can provide.