To answer some of the questions:
A beehive is a porcelain assembly that serves to insulate high voltage as
it
feeds through a chassis wall. Sometimes bigger beehive insulators
are used to run antenna transmission feedlines through walls.
The bleeder resistor network is (or now, was) composed of four
pieces, 100K ohms, 50 watt vitreous enamel OHMITE L50J100K
less than 12 months old, less than 1 hour operation. The resistors
were megged with a DMM before assembly into the plant.
When examined today, one piece was infinite resistance.
A second piece is now 29.2 meg. The third resistor is 110K,
and the fourth, get this: 53.2 ohms.
It sounds to me like there was something of a domino effect.
However, at the actual HV level of 3804 volts, is nine and
one-half mils. This is thirty six watts. Fifty watt resistors
should have handled it, especially mounted with spring clips
in an airflow. If one resistor shorted to 53.2 ohms, the
network then was then 12.6 mils. This would have brought
the dissipation to 48.2 watts. There's a hefty airflow, remember,
so that may or may not have been the trigger for the
other devices to fail.
Comments???
Thanks.
Hal
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