Air Manifold Pressure Input (Signal Input #3; Terminals 48/49); Remote Speed Reference Input (Signal Input #4; Terminals 51/52) - Woodward 723PLUS Original Instructions Manual

Manual 02880
Air Manifold Pressure Input (Signal Input #3;
Connect an Air Manifold Pressure transmitter to Signal Input #3. The input signal
must be an isolated high-quality signal representing the Air Manifold Pressure
signal. By configuration, this signal input allows an air manifold pressure signal to
limit fuel demand. Air manifold pressure is displayed in software adjustable
engineering units on the hand-held programmer and may be re-transmitted (by
configuration) through one of the analog outputs to an external device (meter,
recorder, etc.). Default engineering units setting is 0–50 inches Hg. No
connection is required to this input if this function is not needed by the
application.
Use a shielded twisted-pair cable to connect a 4 to 20 mA current transmitter or a
1 to 5 Vdc voltage transmitter to terminals 48(+) and 49(–). When using a voltage
transmitter, remove the jumper between terminals 48 and 47. An input
impedance of 250  is present when the jumper is installed. Without the jumper
installed, the input impedance is greater than 10 M. This input is not isolated
from the other control inputs and outputs, and an isolation device must be
installed if the transmitter output is not isolated.
A failure of the input signal is detected for input values less than 2.0 mA (0.5
Vdc) and for input values exceeding 21 mA (5.25 Vdc). A configured detected
failure removes the air manifold pressure fuel limit and causes a Status Indication
alarm. The fuel limit removal and Status Indication alarm remain until the failure
is repaired.
Remote Speed Reference Input (Signal Input #4;
Connect a Remote Speed Reference transmitter to Signal Input #4. The input
signal must be an isolated high-quality signal. This signal input allows remote
speed reference set point changes and (by configuration) engine shutdown
protection or alarm protection or both if the input signal fails. The remote speed
reference is displayed in software adjustable engineering units on the hand-held
programmer and may be re-transmitted (by configuration) through one of the
analog outputs to an external device (meter, recorder, etc.). Default engineering
units setting is 0 to 1200 rpm. Remote Speed Reference is activated by
simultaneous and maintained closure of the Raise and Lower discrete inputs
(terminals 33 and 34). The Rated Speed input (Input G; terminal 35) is a
permissive for Remote Speed Reference control and must be closed to permit
Remote Speed Reference control. No connection is required if this function is not
needed by the application.
A failure of the input signal is detected for input values less than 2.0 mA (0.5
Vdc) and for input values exceeding 21 mA (5.25 Vdc). A configured detected
failure will alarm and/or shutdown and remain alarmed and/or shut down until the
failure is repaired and an Alarm Reset is issued.
Woodward
723PLUS/Single Engine Marine Propulsion
Terminals 48/49)
Terminals 51/52)
f the Remote Speed Reference is selected and the input goes below 2
mA, the speed reference will ramp down to minimum speed or shut
down if the control is configured and connected for shutdown.
Default is set not to shut down.
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