______________________________________________
HARRIS
888-9058-001
WARNING: Disconnect and lockout AC primary power prior to servicing
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Figure 3-27. 50 Volt Power Supply Control Board Controls and Indicators
3.17.3 RF PA Module LED Display
3.17.3.1 Green Bar LED
The left half of the green LED indicates that the module is enabled, and the right half
indicates the presence of RF drive. Both halves off indicates that the module has been
disabled due to a “mechanical disable” (initiated by the flapper switch on the front of
themodule), a fault condition (in which the red LED will illuminate and show a fault
code, as described below), or lack of 50 volt supply. If the module is replaced after
removal, a transmitterONcommand is needed to cancel the “mechanical disable” and re-
enable the module. In some cases where transmitter power is significantly less that 30
kW, the PA modules used in the driver stage may be operating at a low power level and
therefore illuminate only half of the green LED, even though proper RF drive is applied.
3.17.3.2 Red Bar LED
If the LED is flashing, the number of flashes indicates the type of module fault:
1. High VSWR
2. RF Overdrive
3. ISO (Isolation resistor voltage sensed due to unbalanced module stages)
4. VOLTAGE (50 volt supply below 44 volts or above 54 volts)
5. TEMP (One or more of the quarter modules inside the module has overheated)