Tracking Error Limit - Parker Compax3 Series Operating Instructions Manual

Parker EME
Behaviour of
"Position reached"
after Power On
Handshake with PLC
for small
positionings
4.1.7.3
Disadvantages
caused by a tracking
error
No position monitoring takes place in status START (E1=24VDC).
Therefore reset the start signal to 0 after the START flank.
O1 is set to "0" after Power On
O1 goes to "1" after the machine zero run (after position 0 has been reached)
START: I1: START Signal
POS: O1: Position reached
Sequence:
PLC
START of a positioning
From position reached = "0" follows:
START = 0
From position reached = "1" follows:
Next START can take place

Tracking error limit

The tracking error is a dynamic error.
The dynamic difference between the target position and the actual position during a
positioning process is referred to as the tracking error - not to be confused with the
static difference, which is always 0. The destination position is always approached
exactly.
The change of position over time can be specified exactly using the parameters
jerk, acceleration and speed. The integrated target value generator calculates the
course of the target position. Because of the delay in the feedback loop, the actual
position does not follow the target position exactly. This difference is referred to as
the tracking error.
In joint operation of several servo controllers (e.g. master controller and slave
controller), tracking errors lead to problems due to the dynamic position
differences, and a large tracking error can lead to positioning overshoot.
I11 T11 192-120101 N6 - March 2004
Setting up Compax3
Reaction Compax3
Position reached goes to "0"
Positioning finished " Position reached =
"1"
Position reached goes to "0"
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