Control functions
7.3 Pulse train input position control (PTI)
SINAMICS V90, SIMOTICS S-1FL6
Operating Instructions, 04/2019, A5E36037884-007
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Calculation formula for the electronic gear ratio
Examples for calculating the electronic gear ratio
Step
Description
Mechanism
Ball screw
Disc table
1
Identify mechanism
•
Pitch of ball screw: 6 mm
•
Deduction gear ratio: 1:1
•
Rotary angle: 360
o
•
Deduction gear ratio: 1:3
2
Identify the encoder
resolution
10000
10000
3
Define LU
1 LU = 1
μm
1 LU = 0.01
o
4
Calculate the travel
distance per load shaft
revolution
6/0.001 = 6000 LU
360
o
/0.01
o
= 36000 LU
5
Calculate the electronic
gear ratio
(1/6000)/(1/1) × 10000 = 10000/6000
(1/36000)/(1/3) × 10000 = 10000/12000
6
Set parameters
p29012/p29013
10000/6000 = 5/3
10000/12000 = 5/6