Hitachi F-4700 - 4.3 Xenon Lamp Replacement

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4.3 Replacement of Xenon Lamp
Replace the xenon lamp with a new one before its cumulative turn-on time exceeds the limit for use.
When the cumulative turn-on time of the lamp reaches the useful limit, vapor and dispersed particles from
the electrodes will adhere to the lamp wall and darken it, causing a decrease in heat dissipation.
The internal temperature (pressure) of the lamp will thus increase abnormally, and there is a danger of
lamp exploding.
Table 4-3
Part No.
Part Name
Useful
Limit
650-1500
150 W xenon lamp
500 hr
250-1600
Long life xenon lamp
1000 hr
WARNING
Cautions on replacement of light source lamp:
 An electric shock due to 30 kV power supplied to the xenon lamp could
result in death or serious injury. Before removing the light source cover
for lamp replacement, turn off power to the instrument and then wait for
at least one hour until the lamp becomes sufficiently cool.
 The xenon lamp becomes very hot during operation and remains hot for
a while after operation. Touching the lamp in this condition could result
in severe burns. Before proceeding to lamp replacement, turn off the
power switch and wait for at least one hour.
 Explosion of the xenon lamp could result in serious injury. Be sure to
wear proper protective gear such as safety goggles, safety mask, thick
long sleeves, and gloves. When mounting the lamp, take care not to
leave fingerprints on the lamp wall.
 If the nut on the lamp base and wiring part is loose, the contact
resistance between them will increase due to poor contacting.
This could generate a large amount of heat to make the lamp extremely
hot, possibly resulting in an explosion. Be sure to tighten the nut
securely.