______________________________________________
HARRIS
888-9058-001
WARNING: Disconnect and lockout AC primary power prior to servicing
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The parallel control lines are used for quick actuation of critical functions, such as ON,
OFF, RF mute, AC_Low and Fault Off. These lines are also the backup control lines in
a Life Support mode when the Main Controller (and therefore the CAN bus) is not
operational. Each board in the control system can independently activate some or all of
the parallel control lines to protect the transmitter in case of a fault or other condition
that may adversely affect the transmitter. These parallel control signals are duplicated in
the CAN messages. The following is a brief explanation of each of the parallel control
lines included in the system control bus.
a.
ON_/OFF: This command corresponds to the transmitter operator pushing the
"ON" or "OFF" button, thereby turning the transmitter on or off respectively. This
signal is high for ON and low for OFF.
b
.
/RESTRIKE (reset): When the transmitter is already turned ON and the
operator presses the "ON" button again, this line will be pulsed low for a
minimum of 100ms. This will cause the slave controller boards to reset any faults
and status and try to return to normal operation. This command is basically a
RESET pulse which will try to turn on any transmitter components which have
faulted off due to a critical fault condition. If they are still faulty, this will be
detected and the component will simply be shut off again. This will not reset or
clear the Fault Log.
c.
/FLT_OFF: This command is initiated whenever a fault occurs that requires all
RF to be shut off and the PA supplies to be disabled. This is a latching type signal
that requires user input to clear the fault and turn the transmitter back on. This
signal is active low. The Main Controller, Power Block Controller, External I/O,
and RF Monitor boards monitor this line and have the ability to activate it if
necessary.
d.
/RF_MUTE: The /RF_MUTE line shuts down all RF output temporarily until
the fault condition is cleared. This is a non-latching signal. The Main Controller,
Power Block Controller, External I/O, and RF Monitor Boards monitor this line
and have the ability to activate it if necessary.
e.
/PS_MUTE: The /PS_MUTE line shuts down the output of the 32 Volt PA
Module Supplies temporarily until the fault condition is cleared. This is a non-
latching signal.
f.
/AC_LOW: This signal is an early warning of an impending loss of control
voltage. When the AC line voltage that powers the LVPS(s) drops below an
acceptable threshold, the board will pull this open collector line low. Phase
samples L3-L1 (C-A) are continuously monitored.