Siemens SIMATIC FM 452, Руководство пользователя

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Machine Data and Cam Data
8-21
FM 452 Electronic Cam Controller
C79000-G7076-C452-04
Range of Values of the Resolution
The range for the resolution must be converted to the basic system of units. The
resolution must be kept within this range by selecting the values “distance per
encoder revolution” and “increments per encoder revolution”.
Based on the systems of units, the ranges for the resolution are as follows:
System of
units Specifications
in... Range for the Resolution
mm 10
–3
mm 0.1 10
–3
mm .... 1000 10
–3
mm/pulse
inches 10
–4
inches 0.1 10
–4
inch .... 1000 10
–4
inches/pulse
degrees 10
–4
degrees
10
–3
degrees
10
–2
degrees
0.1 10
–4
degrees .... 1000 10
–4
degrees/pulse
0.1 10
–3
degrees .... 1000 10
–3
degrees/pulse
0.1 10
–2
degrees .... 1000 10
–2
degrees/pulse
pulses 1 pulse 1
Example
•
An incremental encoder has the following data:
– Increments per encoder revolution: 5000
– Distance per encoder revolution: 1000 mm
– 1 increment = 4 pulses
This results in the following resolution (quadruple evaluation):
Resolution
1000 mm
=
5000 increments
= 0.2000
mm
increment 4 pulses
=
mm
0.0500
pulse
mm
=
0.2000
•
An SSI encoder has the following data:
– Increments per encoder revolution: 4096
– Distance per encoder revolution: 1000 mm
– 1 increment = 1 pulse
This results in the following resolution:
Resolution
1000 mm
=
4096 increments
= 0.2441
mm
increment pulse
mm
= 0.2441