ABB ACSM1 Manual page 81

Distance correction with two probes
The purpose is to measure the distance between two consecutive latches from two
probes and compare it with the distance between the reference positions
PROBE1 POS and 62.18 PROBE2
correction is carried out on the drive actual position
different latch sources (eg, encoder interface digital inputs DI1 and DI2) and latch
commands (eg, rising and falling edge).
In special applications, this correction function can also be executed by using two
consecutive latches from one probe. The latches use the same latch source (eg,
encoder digital input DI1) and different latch commands (eg, rising and falling edge).
Example:
The following figure shows a conveyer system where a box should be positioned.
The conveyer belt is marked every 60 mm.
ENCODER MOTOR
M
3~
Encoder DI1
Encoder DI2
Parameter
60.02 POS AXIS MODE
60.05 POS UNIT
62.14 CYCLIC CORR MODE (4) 2 Probe Dist
62.15 TRIG PROBE1
62.17 TRIG PROBE2
62.16 PROBE1 POS
62.18 PROBE2 POS
POS. If there is a deviation, a corresponding
60 mm
GEARBOX
Setting Information
(0) Linear Positioning between minimum position
MINIMUM POS and maximum position
MAXIMUM POS
(2) Meter All position values are in metres
Distance correction with two probes
(1) ENC1 DI1 _– Rising edge of encoder 1 digital input DI1.
Source of the actual position latching command
(proximity switch signal source)
(3) ENC1 DI2 _– Falling edge of encoder 1 digital input DI2.
Source of the actual position reference latching
command (proximity switch signal source)
0 m Reference position for actual position probe 1
0.060 m (=60 mm) Reference position for actual position probe 2
1.12 POS ACT. The latches use
PROXIMITY SWITCHES
Drive control and features
81
62.16
60.14
60.13