Woodward 2301E-HT, Руководство по эксплуатации продукта

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Manual 35092 2301E-HT Hydro (Francis Turbines)
Woodward 17
cleared and the optional i
nput “Start Permissive” is true (if used), the Gate Limit steps to the “Breakaway
Limit
,” and stays there for the “Hold at Breakaway Time” (see Figure 3-3). Since the control does not have
any speed signal yet, the gates will follow the Gate Limit. After t
he “Hold at Breakaway Time” expires, the
Gate Limit ramps to the “Speed-No-Load Limit” at the “Start Gate Rate.” It will remain there while the control
is synchronizing. At some point during this sequence, the turbine should reach its rated speed and the
2301E-HT
will start controlling speed. If the control does not sense at least the “Start Speed” by the time the
“Time to Start Speed” timer has expired, then the control issues an emergency shutdown due to an
Incomplete Start.
Figure 3-3. Gate Limit
If the turbine has unusually low head conditions and is not able to reach rated speed in order to
synchronize, the control will automatically ramp the gate limit up. This only happens after the “Auto Raise
Delay” time has expired. The rate at which the control raises the gate limit is configured as “Auto Raise
Rate
.”
When the breaker closes, the gate limit steps to the “Maximum Gate Limit.”
If the unit experiences a load rejection, the gate limit will automatically step to the “Speed-No-Load Limit.”
When the 2301E-HT is given a stop command and the unit is on-line, the Gate Limit steps to the actual
gate position and ramps to 0% at the “Stop Rate.” There is an option available to select between a fast
offline stop and a stop at the stop rate. If the FAST OFFLINE STOP? option under the MAIN CONTROL
service header is selected, the gates will close at the hydraulic rate when the breaker is open. If this
option is set false, the gates will always close at the stop rate regardless of the breaker status. If the unit
is off-line when the stop command is given, then the Gate Limit goes to 0% instantly.
The start and stop sequences discussed above occur automatically. The Gate Limit can be controlled
manually at any time if necessary. Two discrete inputs can be configured as Gate Limit Raise and Gate
Limit Lower, or the Woodward Watch Window can be used. The rate at which the Gate Limit will change
is dictated by the “Man R/L Ramp Rate.”
When the control is in Manual, Maintenance, or Follow Mode, the Gate Limit is raised to 100%.
Released