08.2012 Technology Option F01
Siemens AG 6SE7087-6QX70 (Version AN)
SIMOVERT MASTERDRIVES Compendium Motion Control 9-39
Encoder: Resolver
(P171=12 ≅ 4096
increments/revolution)
Gear ratio: 1:10
Diameter of drive roller: 300 mm
How many µm does the slide travel in one encoder increment?
AVWF = number of LUs per position increment
revolutioninc /
1
Diameter
ratio Gear
1
=
inc
m
AVWF
×π××
μ
[]
[]
inc
2
1
m
D
i
1
=
inc
m
AVWF
P171
×
μ
×π×
μ
inc 4096
1
m 300000
10
1
=
inc
m
AVWF
×π×μ×
μ
m 182823,0097118 =
inc
m
AVWF
μ
μ
Resulting Actual Value Weighting Factor (AVWF)
Integer places
3-digit P169
Decimal places
8-digit P170
23 (00)971181
Trailing zeroes must be entered with the decimal place component;
leading zeroes can be omitted.
Examples:
AVWF = 12.3 → P169 = 12, P170 = 30000000
AVWF = 12.00000003 → P169 = 12, P170 = 3
When the actual value weighting factor (AVWF) is specified as a
numerator / denominator, the length units LU are entered in the
numerator and the encoder increments in the denominator.
Example:
A rotary axis is driven via a gear unit with a gear ratio of 1:3. The actual
position sensing function is parameterized such that 2
16
increments
correspond to one motor revolution. One revolution on the load side
must equal 360000LU.
196608
360000
32
360000
AVWF
16
=
⋅
=
NOTE
AVWF as numerator/
denominator