Woodward 2301E-HT, Руководство по эксплуатации продукта

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Manual 35092 2301E-HT Hydro (Francis Turbines)
Woodward 22
Manual and Maintenance is that the control still monitors speed failures and overspeed in Manual control.
Manual control can be enabled using the discrete inputs or Modbus, but Maintenance control can only be
enabled using the Woodward Watch Window.
Maintenance Mode
Maintenance mode should only be enabled when the unit is
de-watered. No speed monitoring functions are active when the
control is in Maintenance mode.
Manual control mode can be enabled when the unit is running or when the unit is stopped. Both Manual
and Maintenance modes follow the actual set point when they are not enabled. This provides a bumpless
transfer into Manual and Maintenance control modes.
The rate at which the manual position moves the gates is the same rate that the Gate Limit ramps up and
down. If the 2301E-HT control is in Manual mode and a Stop command is issued, the unit will stop at the
“Unit Stop Rate.”
The Manual and Maintenance control modes can be forced to go to a preset value. The “Manual Preset
Value” can be adjusted to an exact gate position, and the control can then be forced to go to that set point
by setting “Goto Preset Value” TRUE. This is useful when an exact gate position is needed, and cannot
be easily achieved by using Raise and Lower commands.
The “Goto Preset Value” in Manual and Maintenance modes will
position the gate position at the fastest hydraulic rate possible. No
ramp rate in the control is used to go to this “preset” position.
Auto-Follow Control Mode
The 2301E-HTcontrol for Francis turbines has an Auto-Follow control mode which is used when the
control is used as a backup governor. When this mode has been configured and the discrete input is
closed, the 2301E-HT tracks current gate position and forces all control modes to follow. When the
discrete input opens up, the 2301E-HT will assume control in the control mode that is selected at the time
the “Auto-Follow” discrete input opened up. The same contact that controls the “Auto-Follow” discrete
input must control the transfer relay which switches the actuator control current from the primary control to
the 2301E-HT Actuator Output.
When the 2301E-HT is used as a backup governor, independent speed signals and gate position
transducers should always be used. This will provide true governor redundancy, and eliminate the
possibility of single point failure. If the speed signal or the gate position signal to the primary control fail, it
would be less likely to shut down the 2301E-HT.
When the actuator control current is switched from the primary control to the 2301E-HT, the actuator
current will be zero for an
instant, and the gates will “bump” slightly. The amplitude of the “bump” on the
actuator will vary depending on the relay used to transfer the actuator control current. When the 2301E-
HT is tracking the gate position, the actuator output is forced to 0 mA. This keeps the control from
saturating the output voltage trying to drive the current through an open circuit. Without this, the actuator
would bump open during the actuator control transfer. Forcing the actuator output to 0 mA when the
2301E-HT is not in control forces the gates to bump closed during the transfer from the primary controller
to the 2301E-HT control.
For the 2301E-HT to function as a backup governor, it must be used with a customizable Woodward
digital control as the primary control. This primary control will support the software algorithms to allow the
2301E-HT to be used as a backup governor.
Released