We have some observations concerning damage to other equipment by xenon
light sources, which people may find useful.  The third-party light source
our Company used to supply definitely was much more likely to destroy other
equipment (including ours…) if that equipment was switched on at the time.
A recent case illustrates this very nicely.  A system that had given
trouble-free operation for several years suddenly came back for repair
three times in quick succession.  This turned out to be because there was a
new user in the lab, who thought the recommended sequence was to switch on
the light source AFTER everything else, not before!  That particular light
source design has been known to destroy computers and patch clamp
headstages too.  Needless to say, our customers begged us to do something
about this, and in the end we solved the problem by designing our own light
source, where amongst other remedies we incorporated the igniter in the
lamphouse itself.

We are bemused why this is in general such a big problem, as in our
experience shows it is possible to solve it completely.  But if you do have
a "dangerous" light source, then keeping the igniter unit (if a separate
box) and lamphouse as close to each other and as far away as possible from
sensitive electronics is about the best you can do.  You might also try
some additional screening (e.g. aluminum foil) around the connecting leads,
but this may attenuate the ignition pulse itself – which is typically a few
tens of kilovolts – thereby making it harder to strike the arc.

Martin Thomas


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