Engineering Guide CDA3000
1-17
1 Analysis of task
DE
EN
1
2
3
4
5
6
7
A
Positioning accuracy without position control (Start/Stop mode)
The term positioning accuracy refers to the position deviation at standstill.
The degree of deviation is decisively influenced by the response times of
the control and the drive controller.
The positioning and repeat accuracy is of course also dependent on other
factors such as:
➢
Implementation of the mechanical function
➢
Mechanical system of the pickup
➢
Gearing used
➢
Constant response time of the control
➢
Measurement resolution from position transducer
➢
etc.
A precise analysis is only possible in specific cases.
S
F
= V
max
.
t
RF
S
F
= Positioning error
in mm
V
max
= Velocity
in mm/s
t
RF
= Response error
(terminal
scan cycle) in s
(1) Scan cycle of control terminals on inverter (t
RF
=response error)
(2) Destination position 1
(stop signal comes together with read-in
of control signals on inverter)
(3) Destination position 2
(Stop signal comes directly after read-in of
control signals on inverter)
(4) Slip range
(depending on control mode the braking ramp
is slipdependent)
Figure 1.15 Start/stop positioning
(1)
(2)
(3)
(4)
t
V
max.
