Woodward 2301E-ST, Инструкция по установке и эксплуатации

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Manual 26694 2301E-ST
Woodward 20
Load Sharing Lines Connections (Terminals 10-12)
The Load Sharing Lines provide an analog communication path between compatible controls. The
2301E-ST provides an internal relay for connecting the Load Sharing Signal to the internal circuitry at the
appropriate times. When the internal relay is closed, a green LED will illuminate between terminals 9 and
10. Because the load-sharing-line relay is contained in the control, no relay is required between the
control and the load-sharing-line bus. Use shielded cable and connect the load-sharing lines directly to
terminals 10(+) and 11(–). Connect the shield to terminal 12. When all controls in the system are 2301E-
STs, the shields may be connected continuously between controls. When load sharing with different
controls, do not connect the shields at the point where connections are made to the load-sharing-line bus.
The optional 52G (Generator Breaker) contact is used in conjunction with the control’s load sharing lines.
When isochronous control is selected via the 52G (Generator Breaker) input contact, the unit’s load
sharing lines are enabled.
Discrete Input Connections (Terminals 34-41)
In general, discrete inputs must change state for a minimum of 15 milliseconds for the control to sense
and register a change in state. All contact inputs accept dry contacts. Contact wetting voltage is available
through terminals 31 and 32. If desired, an external 18-40 Vdc power source can be used for the circuit
wetting voltage. In this case terminal 33 (contact input common) must be connected to the external power
source’s negative common to establish a common reference point. Each contact input pulls 3 mA when
closed and requires at least 14 Vdc to recognize a closure command. See Figure 2-2 for wiring
information and
2301E-ST Control Specification for input specifications.
A positive voltage on any discrete input terminal is sensed by the control as a closed contact or “TRUE”
state. With no voltage applied to a discrete input terminal the control senses an open contact or “False”
state.
For power loading reasons, it is recommended that the control’s internal 24 Vdc not be used to power
other external equipment.
Discrete inputs with cable lengths greater than 30 meters that are
used for critical functions, such as emergency stop, should not be
floated in either an on or off state. These inputs should be switched
to +24 Vdc or ground.
External Shutdown Contact (Terminal 34)
Terminal 34 functions as the control’s External Shutdown contact input. Before the unit can be started,
this External Shutdown input command must be cleared. This input can be configured for open-to-
shutdown or close-to-shutdown functionality. The control will initiate an emergency shutdown any time a
shutdown command is given and will immediately step its actuator drive current to zero and, if so
configured, change the state of its shutdown output. This input is typically tied into the system’s trip string
to enable it to react to any system trip command.
Reset Contact (Terminal 35)
Terminal 35 functions as the control’s “Reset” contact input. The external Reset contact is used to reset
any latched alarms and/or shutdown conditions, if the condition has been cleared. If the alarm or
shutdown condition has not been cleared the Reset command will not affect its status. To issue a reset,
the contact must be pulsed to close. No action is taken if contact is either left closed or open after pulse.
If the RUN and Start contact inputs are closed (activated), and the
Reset contact input is pulsed closed to open, the turbine may start!
Released