AR 10006896, Руководство по эксплуатации и обслуживанию

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Model 500T2G8
12 Rev E
Color Function
International Harmonized North American
Brown Black Line
Blue White Neutral
Yellow/Green Green Safety Ground
CAUTION:
Connect plug to J1 and secure plug with bracket only when no AC is
supplied to the cord.
Some amplifiers for the North American market may be provided with a suitably terminated power cord.
3.2.5 RF Output Connections
The RF output coaxial connector is 7-16 DIN.
CAUTION:
Never operate the TWTA without a matched output load rated for at least
1000 watts, continuous. The TWTA is not provided with an output
isolator. Full-reflected power may irreparably damage the TWT. Even
with no drive, “looping” oscillation can result in RF output high enough to
damage the tube if it is operated without a load. The VSWR detection
and foldback circuit is provided to protect the tube from progressive
failure or mismatch of the output load; it should not be relied on for
protection from the absence of a load.
If an external isolator is installed at the output of the TWTA, either the isolator should have a load capable of
dissipating the full output of the TWTA or the isolator load should be provided with a temperature sensing
switch. The temperature switch should be normally closed, self-resetting, and with a temperature rating such
that there is no possibility of damaging the load by overheating before the switch opens. The TWTA may be
interlocked with the switch by connecting it between pins 10 and 11 of the external interlock connector (J2).
If no external isolator is used, retain the jumpers between pins 3 and 4 and between pins 10 and 11 in the
mating connector for J2. See Section 3.2.6, External Interlock Connector, below.
If an external absorptive filter is installed at the output of the TWTA, either the absorptive filter should be
capable of dissipating the full output of the TWTA or it should be provided with a temperature sensing switch
as described above.
3.2.6 External Interlock Connector
The TWTA is provided with an external interlock capability via a 15-pin female D-sub connector, J2. To
enable the high voltage power supply, it is necessary to provide continuity between J2 pins 3 and 4. If the
amplifier shuts down because the interlock was opened, it will be necessary to reset the system to return to
standby (see
System shutdown screen in Section 3.4). Users may adopt this interlock feature to turn off the
high voltage power supply and disable the RF output either for equipment protection or as a backup for
personnel protection.