U Page 26
Digital controller RK 4004
Amplification too high
Amplification too low
Amplification right
.1.3. prop range +/-
On
proportional
actuators the amplification of the position con-
troller is set via the two parameters ".1.3. Prop range ±" and ".1.6.
velocity auto". On
integral
actuators amplification is set via the
two parameters ".1.3. Prop range ±" and ".4.5. prop stroke".
With regard to the following considerations please always take into
account that a change to one of the two parameters will always in-
fluence amplification.
Amplification is correctly set if, after brief overshooting the error is
corrected. If the position controller is set with too great a degree of
sensitivity, the guider will overshoot as well. In the case of too little
amplification the control loop will be too slow. Optimum amplification
may be determined with a characteristic curve tracer. In practice, am-
plification may also be determined by trial and error.
Proportional actuator:
The smaller the set proportional range at a constant maximum posi-
tioning velocity (Parameter ".1.6. velocity auto") is, the greater the
amplification of the web guider will be.
A negative proportional range causes negative amplification, the
effective direction is thus inverted in automatic mode.
Positioning velocity
.1.6. velocity auto
20 mm/s
Proportional range
.1.3. prop range ±
2,0 3,5
Control deviation of
1.5 mm
Set position
(sensor measuring range cen-
ter )
established correction
positioning velocity de-
pending on proportional
range
Velocity correction
Control deviation
15 mm/s
8 mm/s
