Manual 85204
ProTech 203 Overspeed Protection System
Woodward
19
When the "TIMER STARTS ON RESET" option is set to "YES", the "ALM IF SPD <
MPU FAIL SETPT" option is active. If "ALM IF SPD < MPU FAIL SETPT" option is set to
"YES", the alarm relay de-energizes whenever speed is below the MPU fail set point.
The start key has no effect when the "TIMER STARTS ON RESET" option is set
to "YES".
Table 4-2. Start Mode Options
TIMER
STARTS
ON
RESET
Option
ALM IF
SPD <
MPU
FAIL
SETPT
Option
NO
NO
Default operation. "Reset" resets trip and alarm condition. "Start" begins
MPU fail timer.
NO
YES
Same as above. The ALM IF SPEED > MPU FAIL PT option has no effect
if the TIMER STARTS ON RESET option is set to "NO".
YES
NO
MPU fail timer starts on Reset. Start button and contact input have no
effect. Speed < MPU fail point is not an alarm condition. Similar to
ProTech systems 9905-869 through 9905-886.
YES
YES
MPU fail timer starts on Reset. Start button has no effect. Contact input
provides trip input which is independent of the MPU fail timer. The alarm
is true whenever the speed is below the MPU fail set point. Similar to
ProTech systems 9905-750 through 9905-756, and 9905-989 though
9905-999.
Normal Operation
Each unit in the ProTech system continually monitors speed for an overspeed
condition (present speed > TRIP SPEED SETPOINT) or for a loss-of-signal condition.
The peak speed is updated whenever the present speed exceeds the peak speed.
If an overspeed occurs, the unit trips. After the trip occurs, the peak speed
continues to be updated and is stored in non-volatile memory. Non-volatile
storage means that even if power to the unit is lost, the peak speed can be
retrieved later. Peak speed is not stored in non-volatile memory if an overspeed
condition has not occurred.
To reset a unit's peak speed, press the menu key repeatedly until PEAK SPEED
is displayed. (If the unit is tripped, it must first be reset by pressing the reset key.)
Place the key switch in the PROGRAM position, then press the reset key. The
peak speed is set equal to the present speed. Return the key switch to the
MONITOR position.
AN MPU loss-of-signal occurs when a sudden loss of speed is detected. When
an MPU frequency of less than 100 Hz is measured, the previously measured
speed is checked. If it was greater than 120 Hz, the MPU is assumed to have
failed. The alarm relay de-energizes, and the MPU FAIL LED turns on and
remains on until the unit is reset or until power is cycled. If the TRIP ON MPU
FAILURE option is set to "Yes", a trip occurs. When a normal rolldown occurs,
the alarm relay does not de-energize, the MPU FAIL LED does not turn on, and
no trip occurs.
To perform a lamp test, press the menu key repeatedly until "PRESS START
FOR LAMP TEST" is displayed. Pressing the start key then illuminates all LED's
and causes solid block characters to be displayed on the screen for
approximately 2 seconds.
Содержание ProTech 203
Страница 39: ......
