Simrad Robertson AP9 Mk3, Instruction Manual, Page: 147 / 202

Installation
20169223D
5-57
Tunnel Thruster function
The operation of tunnel
thruster is used for
maintaining the heading
with nearly no speed.
The typical tunnel thruster
characteristic can be
illustrated by the following
graph:
The illustration shows that
in order to obtain 50%
thrust, the control signal
must be nearly 8V (appr.
75% of the 10V). To obtain a
thrust amount, capable of controlling the vessel, a certain minimum
level of thruster control signal should be applied to the thruster for a
minor heading error.
Special parameters for Thruster Function appears in INFO LOOP II
when Thruster Function switch is set to THRUSTER.
Thruster Deadband
The Deadband determines
the amount of error signal
(in degrees) before
command is applied to the
thruster. The example
shows ±5 degree deadband.
No deadband is shown by
the dotted line.
Minimum Thrust
The Minimum Thrust
determines the amount of
power (in % of maximum
control signal) that is applied as
"first command signal". The
example shows 30% of the
control signal applied as
minimum thrust.
The dotted line shows the
output signal for Minimum
Thrust "OFF".
U
+10V
Linear function
Thrust
100% 50%
Appr. 8V
50% 100%
5V
U
+10V
(100%)
Deadband
3° 3°
-10V
Heading error
Deadband OFF
U
+10V
(100%)
30%
Minimum
thrust OFF
Heading error