UNSTABLE ARC OR FLICKER
Overcoolingcontinued
and
airborne searchlights that operate without cooling the envelope. They have
water-cooled designs to maintain the seals and electrode shaft temperatures at
a desired level as dictated by the bulb's design. If the envelope of the bulb
is designed properly, it will require no forced-air cooling. By blowing or
exhausting large amounts of air over the cathode side of the envelope, you can
actually create an unstable condition and affect the integrity of the cathode
electrode.
Picture the envelope of your bulb as a chamber that contains
heat and pressure - more precisely, a plasma thermal are chamber. If one side
of the chamber is much more cooled than the other side, you will set up
excessive and even unpredictable gas flow patterns. It's kind of like the same
thing that creates tornadoes, This high density swirling action can and will
interfere with the plasma are between the electrodes and create an annoying are
instability.
Poor electrical connections - Another
source of possible flicker is a poor electrical connection with or within the
lamphouse or power supply, As these connections heat up, while the lamp is
operating, the electrical conductivity of the connection decreased due to
thermal expansion which creates a loose electrical connection. Do yourself a
favor and periodically check the connections when performing periodic
maintenance.
RECORDS
Be smart and keep bulb and lamphouse performance records. When
you do encounter a problem, it will be much easier to troubleshoot if you have
some system history.
You'll also find that
this will eliminate a bulb or system lllanufacturer's blame on the other guy
and will give you the analytical data you need to make a decision on your own,
Believe me, it's not that complex to solve if you have some history or data to
reference in making your decision,
* * * *