Safety Critical Components For Xx93 Monitors - Ceronix 1493 Service Manual

Safety Critical Components for XX93 Monitors.

Components marked by the symbol ! have special characteristics important to safety.
When replacing any of these components, be sure to use the parts specified in the parts
list.
An example of how the critical components are marked in the Master Part List is shown
below. See the Master Part List for specifying critical components.
∆ Bd.# Part No. Bd. Sch. Ref.
! 102 CPC1027 D2
CERONIX XX93 Monitors MUST USE AN APPROVED ISOLATION
TRANSFORMER.
The monitor chassis must be connected to earth ground via a common connection
in the system which contains the monitor.
X-radiation is produced by electrons colliding with the phosphor and shadow mask at the
front of the picture tube. The X-radiation emanating from the front of the picture tube is
highly reduced due to the shielding affect of the leaded glass face.
It is also produced at the anode bulb contact. The X-radiation emanating from the anode bulb
contact is much higher than from the face due to less shielding.
X-radiation is directly proportional to beam current. It doubles for each 1.3KV increase of
the EHT voltage at the face and also doubles for each 3KV increase of the EHT at the anode
bulb contact.
From this information, it should be noted that when servicing monitor electronics, where the
back of the picture tube is facing the service person, that the beam current should be turned
down to avoid excessive exposure.
Due to the increase in X-Radiation emission with increase of EHT voltage, it is important that
the EHT voltage is checked.
To measure the EHT voltage: Connect the (-) lead of a volt meter to the monitor chassis so
that a reliable connection is made. Connect a high voltage probe to the (+) input of the meter
and at the anode contact of the picture tube.
The EHT should not exceed 26KV at 0 beam current.
PRODUCT SAFETY NOTE:
Description
HH8 6,800pF ±5%, 100V, Film
CAUTION:
X-RAY NOTE:
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