6
6.2
Positioning mode (P0700 = 3, from SW 2.1)
6-392
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SIMODRIVE 611 universal Description of Functions (FBU) – 04.05 Edition
Reference cams
Motion
ÎÎÎ
ÎÎÎ
Motor and
encoder
e.g.:
P0662 = 78
input I2.x
with function No. 78
(reference cams,
refer to Chap. 6.4.2)
I2.x
M
G
Fig. 6-20 Mounting a reference cam
The following factors influence how the drive identifies the reference
cam from a time perspective:
Accuracy or time delay when detecting a reference cam
Delay at the input, position controller clock cycle, interpolation clock
cycle, ...
!
Warning
If the reference cam is not adjusted, so that at each reference point
approach, the same zero pulse is recognized for synchronization, then
an ”incorrect” machine zero point is obtained.
Recommendation:
Experience has shown that it is best to adjust the reference cam edge,
required for synchronization, at the center between two zero pulses.
Example when adjusting the reference cam
After the reference point approach, the distance between the reference
cams and the zero pulse can be read in P0172.
This means that when the distance between 2 zero pulses is known,
the reference cam offset travel can be calculated.
Reference cams
P0172
Distance
between 2 zero pulses
–”–
–”–
Adjustment goal:
The reference cams
should be shifted, so that half
of the distance between
2 zero pulses is located in the
P0172
Zero
pulse
Fig. 6-21 Adjusting the reference cam
Adjusting the
reference cam
6 Description of the Functions
01.99
! not 611ue !