Woodward ProTech 203, Руководство по эксплуатации

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ProTech 203 Overspeed Protection System Manual 85204
20 Woodward
Overspeed Test
The overspeed test function is activated when the keyswitch is in the PROGRAM
position and the operator presses and holds the OVSP TEST button on the
touchpad. The microcontroller switches the source of the MPU signal from the
MPU input to an on-board oscillator. The test speed is annunciated on the LCD.
If the test speed is adjusted above the trip set point, using the Test Frequency
potentiometer on each unit, a trip occurs. MPU loss-of-signal checking is
disabled, and the peak speed value does not change during overspeed test.
When the OVSP TEST button is released, the microcontroller switches the
source of the MPU signal back to MPU input and normal operation is restored.
Each ProTech unit must be reset to clear its trip condition.
Each individual unit may be tested as described above while the
entire system remains on-line. In this case, the two units not being
tested take over full control of the overspeed protection for the prime
mover.
It is recommended that the overspeed test be performed on each unit
on a weekly basis and that an actuating equipment integration
assessment be performed any time the prime mover is taken off-line.
Hardware Faults
If the microcontroller determines that the EEPROM is not responding correctly, a
trip occurs. The trip cause is annunciated as "HARDWARE FAULT". If this type
of fault occurs, reset the unit. If the fault continues to occur, replace the unit and
return it for repair.
If the microcontroller determines that the data in EEPROM has been corrupted,
the display shows "EEPROM DATA LOST". If this type of fault occurs, reset the
unit. If the fault continues to occur, replace the unit and return it for repair.
The microcontroller monitors an interlock signal which indicates that the internal
hardware cables are connected correctly. If this signal indicates a missing
interlock, a trip occurs. The cause of the trip is annunciated as "INTERLOCK
FAULT". If this fault occurs, check all cable connections.
If a monitor circuit determines that the microcontroller is not functioning, a trip
occurs. The CPU FAIL LED turns on. If this fault occurs, replace the unit and
return it for repair.
Table 4-3 provides a summary of possible trip causes.
Table 4-3. Trip Causes
Display Shows Cause
MPU>TRIP SETPT Speed has exceeded the TRIP SETPOINT value.
OVERSPEED TEST Speed exceeded the TRIP SETPOINT value
during an overspeed test.
MPU FAIL TIMEOUT After START, speed did not reach the MPU FAIL
SETPOINT within the MPU FAIL TIMEOUT time.
MPU FAILED A sudden loss of speed occurred while running.
NO MPU SIGNAL The contact input was open while speed was
below the MPU FAIL SETPOINT, and the TIMER
STARTS on RESET option is set to "Yes".
HARDWARE FAULT The unit has an internal hardware problem.
INTERLOCK FAULT An internal cable is disconnected.