On 05/02/2018 17:54, philo wrote:
Because he heard I was good at fixing things, a guy with a
silk-screening business asked me to look at one of his lights.


It's a backup unit so not crucial, but he said no one in town can fix it
and it would cost a fortune to send it back to the factory.
He was told that it's old and obsolete and even the factory would
probably not be able to repair it anyway.


I told him I'd look at it, but there was a good chance it would be ready
for the scrap heap when I got done.


It had "complex" circuitry and as far as I could tell, it first applied
a "lower" voltage to the bulb (perhaps 230 volts). Then after it warmed
up, would boost the voltage to 600 or so.


I know nothing about gas discharge lights, I was wondering if anyone
here has an info. As far as I could tell, they emit a lot of UV.


He told me that when he first started his business, he had a home made
500watt halogen light that worked fine...it just took 15 minutes to do a
burn and he wanted to do things a bit faster.


After I gave up trying to repair it, I removed the bulb and sockets and
retrofitted halogen fittings and a 230v 1500 watt bulb.


He has not tested it yet, but the thing is too bright to even look at so
it should work.


But still I'm curious about the gas discharge lamp.

It's tubular and has no filament.

Difficult things to test other than by substituting , both ways.
Be very aware, the strike voltage is of the order 5,000 volts, repeated
until something like full current passage.