Woodward 721 - 11. Tach at 4 Ma Output; 12. Tach at 20 Ma Output; Idle Speed; Load Transfer Rate

721DSC for Marine Propulsion Application Manual 26004
Woodward
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2. Idle Speed
Idle Speed is the lowest speed reference selected when the Start Pos/Idle contact
(external contact B) is closed.
3. Rated Speed
Rated Speed is the speed reference selected when the Shaft Generator Operation Mode
contact (external contact G) is closed.
4. Raise Limit
Raise Limit is the maximum speed reference setting. It is used to limit the Raise Speed
command and the Remote Speed Reference to a maximum. It normally is set at the
maximum rated engine speed.
5. Raise/Lower Rate
Raise/Lower Rate is the rate at which the speed reference is ramped when using the
Raise command or the Lower command as well as when the Remote Speed Setting input
is changed in the increase or decrease direction. A step change on the remote input does
not cause an immediate change in the reference, which is ramped to the new setting at
the Raise/Lower Rate.
6. Load Transfer Rate
The Load Transfer Rate is the speed raise/lower rate which is used for generator load
transfer or for generator synchronization. This speed change rate is selected
automatically when the engine is operated in the KW droop mode. Normally, the speed
change rate of Load Transfer Rate is less than that of Raise/Lower Rate.
7. Spd Set at 4mA
Spd Set at 4mA is the speed reference when the remote speed setting input is 4 mA.
8. Spd Set at BP, mA
Spd Set at BP, mA is the remote speed setting signal in mA at the break point at which
the speed reference slope to the remote speed setting input changes.
9. Spd Set at BP, RPM
Spd Set at BP, RPM is the engine speed in RPM at the same break point above. The
Speed Reference moves between ‘Speed Set Point at 4mA’, ‘Speed Set Point at
Breakpoint’ (above), and ‘Speed Set Point at 20mA’ (below).
10. Spd Set at 20mA
Spd Set at 20mA is the speed reference when the remote speed setting input is 20 mA.
11. Tach at 4mA Output
Set this set point to the engine speed in RPM when the tachometer output channel
outputs 4 mA.
12. Tach at 20mA Output
Set this set point to the engine speed in RPM when the tachometer output channel
outputs 20 mA.