Comtech EF Data XTD-400C Operation And Installation Manual page 76

Fault Log
Entry
MISPHA F Missing Phase.
Ovrdrv A Input Over Drive Alarm
reported by Power Supply.
Ovrdrv F Latched Input Over Drive Fault
reported by Power Supply
PHASEQ F Phase Sequence Fault:
PWR MTCH RF Power Mismatch Fault on
dual tube units
PwrLim F Software Power Limit Fault
RfltPwrA Customer Settable High
Reverse RF Power Alarm
RfltPwrF Customer Settable High
Reverse RF Power Fault
Thrm2IlK TWT Thermal Interlock for
TWT 2 in dual tube units
MNC-0400-048
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Table 1TWTA Fault Log Troubleshooting
Description
F = Fault; turns high voltage off.
12 of 14
Operation, TWTA ODU Amplifier
Possible Cause of
Fault
One of the phases Verify A/C wiring to
of the 3-phase A/C unit.
input is missing.
Input drive level is Lower input drive
too high. level.
Input drive level is Lower input drive
too high. level.
The three phases of Re-wire A/C power
the 3-phase A/C cable.
input are wired
incorrectly.
The two TWT's are Call customer
out of phase with service.
each other.
The RF output 1. Change the RF
power has Limit. 2. Reduce the
exceeded the set input drive level. 3.
power limit. Change the amount
of attenuation that
can be added
before a fault
occurs. 4. Disable
the feature.
The reflected RF Check for properly
power level connected
exceeds the limit waveguide, and a
set. properly terminated
load.
The reflected RF Check for properly
power level connected
exceeds the limit waveguide, and a
set. properly terminated
load.
The TWT Check cooling
temperature has system for air
exceeded the blockage and
manufacturer's max properly operating
level. fans.
Action Needed to
Clear Fault
Revision B