ABB ACSM1 - Page 78

Drive control and features
78
t
1
: Rising edge of encoder digital input DI1 signal (proximity switch signal) is
detected. The actual position is 20 mm (stored to signal 4.04 PROBE2 POS MEAS).
The distance between the follower position and the actual position is 15 mm - 20 mm
= - 5 mm
t
2
: Rising edge of encoder digital input DI2 signal (proximity switch signal) is
detected when the actual position is 40 mm (stored to signal 4.03 PROBE1 POS
MEAS).
According to parameter 62.16 PROBE1 POS and 62.18 PROBE2 POS settings, the
follower should be 10 mm behind the master.
The following correction is calculated and stored as reference error 4.05 CYCLIC
POS ERR:
(62.18 PROBE2 POS - 4.04 PROBE2 POS MEAS) - (62.16 PROBE1 POS - 4.03
PROBE1 POS MEAS) = (25 mm - 40 mm) - (15 mm - 20 mm) = -10 mm
t
3
: Error has been corrected and the follower is 10 mm behind the master. Cyclic
function is ready for a new correction if necessary.
40 mm
t
2
t
3
20 mm
35 mm
t
1
4.03 PROBE1 POS MEAS
4.18 SYNC ERROR
1.08 ENCODER 1 SPEED
Encoder DI1
Encoder DI2
4.04 PROBE2 POS MEAS
1.12 POS ACT
4.16 SYNC REF GEARED
30 mm
25 mm