CPI VZU-6994, Руководство пользователя

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Power Monitor Module
The RF power monitor assembly receives signals from the forward and reflected power
RF detectors for use in fault/alarm sensing and forward power metering. The reflected RF
fault sensor/recycle circuit protects the TWT against excessive reflected power due to
abnormal waveguide or antenna conditions. Additionally, the forward power metering
circuit measures both continuous wave (CW) and peak RF signals. Also included is a
forward power low RF alarm circuit, which compares the output power with a user-
settable low RF set point and triggers an alarm, should output power fall below this level.
Mechanical Design
General
The VZU-6994 is packaged in a standard rack mounted drawer measuring 19" wide by
5.25" high and 24" deep (plus connectors, fan and air duct adapters). The unit is cooled
via a forced-air cooling system consisting of two axial fans, an air filter and an exhaust
duct. Allowances are made for 0.10" H
2
0 drop due to customer ducting losses.
LRU Philosophy
The CMPA utilizes a modular design approach incorporating LRUs for ease of
maintainability in the field. The maintenance concept employed in the VZU-6994 is to
localize a malfunction or circuit failure down to the level of an LRU, extract the LRU and
replace with an equivalent part provided in the spares kit. This procedure can be
completed in the field without resorting to the costly practice of returning the entire
CMPA to the depot for servicing. The philosophy is to configure the CMPA LRUs as
building blocks with a specific function that can be monitored by sensors and fault
indicators on a real-time basis.
Ku-Band CMPA 04/08 TD-67 Page 7