Manual 35092
2301E-HT Hydro (Francis Turbines)
Woodward
12
The first analog input can have a special function: if the Speed Bias
is configur
ed to come from an analog source and it’s going to be
used only for synchronizing, then this analog input is used as a
Speed Bias input if the generator breaker is opened and one of the
options listed above if the generator breaker is closed.
The second analog input will always be the selected function.
Discrete Inputs
Eight discrete inputs (on/off switches) are available. Five of them are dedicated to the following functions:
Run/Stop, Raise Speed/Load, Lower Speed/Load, Generator Breaker Status, and Emergency Shutdown.
The other three discrete inputs on the 2301E-HT for Francis turbines are configurable.
The following options are available:
Manual Gate Control Enable
: When this discrete input is closed, the gates can be controlled
“manually” with the Raise and Lower discrete inputs. Manual Gate control can also be enabled
through Modbus.
Pond/Tail Level Control Enable
: When this discrete input is closed, the control will switch into
pond/tail level control. The Raise and Lower discrete inputs will raise and lower the pond level set
point. Pond/Tail Level Control can also be enabled through Modbus.
Auto Follow Enable
: This input should be used when the 2301E-HT is being used as a back-up
governor. When this discrete input is closed, the control will track current gate position in all control
modes, and the Raise and Lower inputs are disabled. When this discrete input opens, the 2301E-HT
will assume control of the unit in whatever control mode is selected. Auto Follow control can also be
enabled through Modbus.
Gate Limit Raise & Gate Limit Lower
: When one of these discrete inputs is closed, the Gate Limit
ramps up or down at a configurable rate. The 2301E-HT is designed so that Gate Limit control is not
necessary, but it is available if required by the application. Gate Limit Raise and Lower can also be
done through Modbus.
Creep Input #1 & Creep Input #2
: Creep detection requires two inputs from proximity probes (or
from ZVPU interface modules). By monitoring the Creep #1 and Creep #2 discrete inputs, the control
can detect when the unit is creeping.
Dirty Oil Switch Input
: This input is intended to be used when a dirty oil indicator has a contact
switch on it. When this discrete input closes, it triggers the governor alarm “Dirty Oil Filter,” and the
alarm is also sent to Modbus.
Governor Reset
: All shutdowns and alarms are latched until the fault condition clears and the
control is reset. When this input is closed, it resets the control. The control can be reset through
Modbus or by using the Woodward Watch Window.
External Start Permissive
: After a start input, the control waits for a momentary closure of this
discrete input before starting the unit if this function is used or this input must be closed before the
start command.
Speed Bias Raise & Speed Bias Lower:
When one of these discrete inputs is closed, the Speed
Bias internal ramp ramps up or down at a configurable rate. For using these discrete inputs the
speed bias source must be configured to digital. Speed Bias Raise and Lower can also be done
through Modbus.
Baseload Enable:
This input is used to enable the Baseload control mode. In Baseload the
generator load will stay in a determined setpoint either by the Raise Speed/Load inputs, or by a
remote Baseload input or by a Baseload Modbus reference. The following conditions must also be
present in order to the baseload control be enabled: the generator breaker must be closed and the
manual, auto-follow and level control modes must be disabled. Baseload Enable can also be done
through Modbus.
Unload:
When in parallel and baseload operation, it may be desired to unload the engine and open
the generator breaker. When the unload contact is closed (rising edge triggered) the control starts to
slowly decrease the load reference and, either when it reaches a minimum value (unload trip level)
or a certain maximum delay after the reference reaches the unload trip level (configurable), it gives
Released
