Amplifier Research 200T4G18, Руководство по эксплуатации и обслуживанию

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Model 20T4G18
3.2.4 AC Line Power Connections
AC line power connection to the TWTA is made at the AC inlet J1, which is a female IEC-320 connector. A
line cord suitable for the type of AC outlet used, and consistent with local electrical codes, must be obtained
to mate with J1. Minimum wire size for the line cord is 18 gauge.
TWTAs destined for the North American market are provided with a terminated 3-wire cord. It plugs into
normal 120 VAC single phase outlets. The amplifier will operate from any line voltage between 99 and 260
VAC.
3.2.5 RF Output Connections
The RF output coaxial connector is type TNC female.
CAUTION:
Never operate the TWTA without a matched output load rated for at least
100 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 3 and 4 of the external interlock connector (J2). If
no external isolator is used, install a jumper between pins 3 and 4. See section 3.2.6, External Interlock
Connector, below.
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). There is an internal jumper between J2 pins 1 and 2; a
continuity check through these pins can be used to verify the presence of the amplifier in the instrumentation
system. Users may adopt this interlock feature to disable the RF output for either equipment protection or as a
backup for personnel protection.
CAUTION:
Do not rely on the external interlock for personnel protection. The intent
of the external interlock feature is to disable the RF output for equipment
protection. Use proper operating and safety procedures to insure that
power is removed for personnel safety.
10 Rev B
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