Woodward 2301E-ST, Инструкция по установке и эксплуатации

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Manual 26694 2301E-ST
Woodward 77
4. Start / Unload. The Discrete Input-C (Terminal 36) Start / Unload should be toggled to start the
turbine. If this input is being used as a Load / Unload contact, do not toggle this
input to start the turbine. By closing this contact, will start the turbine and if this a
generator application will also soft load the generator from an isolated bus.
The start mode of operations determines what the actuator will do when a start
condition is given. The open of valve limiter may be aborted at any time by
issuing valve limiter raise or lower commands, or an emergency shutdown.
Automatic Start. The Valve Ramp Limiter will ramp up to its maximum limit after the Start
Command is issued. The speed reference increases to the rated speed by the
programmed sequence. Once the turbine speed reaches the speed reference,
the valve ramp limiter goes out of the way (100%), and the speed is controlled by
the PID. The speed will continue to ramp to rated speed.
Figure 4-2 is an example of an automatic start sequence.
1.
Close the Run / Shutdown discrete input, toggle the Reset discrete input,
and close the Start / Unload contact.
2. The speed reference ramps up by the programmed rate.
3. As the turbine speed increases, the PID controller will take over control,
and the valve ramp jumps to 100%, which is out of the way.
4. The speed PID controller then ramps the speed reference at a controlled
rate to the rated speed setpoint. At any time, momentarily closing the
Speed Raise or Speed Lower discrete input will stop the turbine from
ramping. This allows the operator to heat soak the turbine at various
speeds. To continue the ramp, manually close the Speed Raise Contact.
5. If for some reason the turbine shuts down, due to a 2301E-ST shutdown,
and the Run and Start contact inputs are closed, a toggle on the Reset
contact will initiate the start sequence.
Figure 4-2. Automatic Start-Up
Released