Figure 3-1. Speed Sensor Roll-Off Filter - Woodward 723PLUS Technical Manual

723PLUS Digital Marine Control
For single speed input applications, either input may be used. The unused speed
signal input will be failed when the engine is running.

Figure 3-1. Speed Sensor Roll-off Filter

More Speed Inputs
All the speed signal configurations are located in the A**CONFIG SPD
CONTROL** configure menu. 01 GEAR #1 TEETH (under header, A**CONFIG
SPD CONTROL**) should be set to the number of gear teeth on the gear where
speed sensor #1 is installed. If the gear is not rotating at the same speed as the
crankshaft, the gear teeth must be adjusted accordingly. In this case, set the
gear teeth equal to the number of teeth that will pass the MPU in one complete
engine revolution.
Speed Signal (Hz) = Gear Teeth * Engine rpm / 60
02 GEAR #2 TEETH (under header, A**CONFIG SPD CONTROL**) should be
set to the number of gear teeth on the gear where speed sensor #2 is installed. If
the gear is not rotating at the same speed as the crankshaft, the gear teeth must
be adjusted accordingly. In this case, set the gear teeth equal to the number of
teeth that will pass the MPU in one complete engine revolution. This gear must
rotate at the same speed as the gear used for speed sensor #1.
The number of gear teeth is used by the 723PLUS control to convert
the pulses from the speed sensing device to engine rpm. To prevent
possible serious injury from an overspeeding engine, make sure the
control is properly programmed to convert the gear tooth count into
engine rpm. Improper conversion could cause the engine to
overspeed.
Should the engine speed fall below the failsafe speed, the 723PLUS will consider
the speed sensor failed and shut down the actuator output. The failsafe speed is
automatically calculated and set to 5% of the value entered in for rated engine
speed. The speed sensors also have a failsafe voltage level. The 723PLUS
control must have at least 1 Vrms MPU voltage to operate. An amplitude less
than 1 Vrms is considered to be a failed speed signal, and the 723PLUS control
will go to minimum fuel.
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Manual 26482
Woodward