Woodward ProTech 203, Руководство по эксплуатации

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Manual 85204 ProTech 203 Overspeed Protection System
Woodward 17
Operation
As used in the following discussions, "trip" refers to the action of an
individual speed-sensing unit in the ProTech 203 system as it de-
energizes the alarm relay, and turns on the TRIP LED, and de-
energizes its voter relays (de-energize-to-trip versions) or energizes
its voter relays (energize-to-trip versions). The trip cause becomes
the currently displayed parameter. Once a unit is tripped, it remains
tripped until reset or until the power is cycled.
Start-up
The ProTech 203 system allows two methods for turbine start. The "TIMER
STARTS ON RESET" menu option determines which method is used. The
default setting for this option is "NO", which provides separate reset and start
functions. When this option is set to "YES", a combined reset/start function is
provided by the reset key or remote reset contact. The two methods are
described below. Table 4-2 provides a brief summary of the two start
configuration options.
Method 1
"TIMER STARTS ON RESET" = "NO". MPU fail timer starts when start key is
pressed or when the contact input opens.
See Figure 4-2 for a block diagram of this method. First, any trips or alarms are
cleared by pressing the reset key or by momentarily closing the reset contact.
Before the MPU fail timer is started, and while it is running, the MPU fail trip is
overridden. When the turbine is ready to be started, the MPU fail timer is started
by pressing the start key, or by momentarily opening the contact input. The timer
expires when it reaches the MPU fail timeout value. If speed does not exceed the
MPU fail set point before the timer expires, the unit trips. The MPU fail LED turns
on and remains on until the unit is reset.
Figure 4-2. Method 1 Block Diagram
Compare
Timer
START
CLEAR
EXPIRED
Latch
SET
CLEAR
TRIP
MPU
START
RESET
Speed < MPU Fail Setpoint
Speed > MPU Fail Setpoint
Compare
MPU
Fail
Detect
Speed > Trip Setpoint
MPU Fail
Setpoint
Value
MPU Fail
Timeout
Value
AND
AND
OR
Trip Setpoint
Value