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3 resolution of an encoder revolution, 5function blocks – Lenze E94A User Manual

Page 514

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5

Function blocks

5.136

L_SdSetAxisData - machine parameters

514

Lenze · 9400 function library · Reference manual · DMS 6.7 EN · 08/2014 · TD05

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5.136.3

Resolution of an encoder revolution

C04249 serves to set the resolution - tailored to the application.

• The preset resolution of 16 bits/revolution is sufficient for standard applications.

[5-107] Example: Standard resolution (16 bits/revolution)

• For higher-order applications, a higher resolution of the position values may lead to considerab-

ly improved control properties and positioning accuracies.

• Finer resolution of the position targets  improved positioning accuracy
• Finer quantisation of the setpoints and actual values  higher control quality
• Higher loop gain can be adjusted  less following errors

• However, a higher resolution results in a restricted number of encoder revolutions and only

smaller traversing paths can be displayed.

[5-108] Example: Higher resolution (22 bits/revolution) with restricted traversing range

Tip!
The way how to detect the optimum resolution of the position values is described in the fol-

lowing subchapter "

Detecting the optimum resolution

".

( 516)

Sign bit

Number of revolutions: 15 bits ≡ ±32767 revolutions

Resolution of an encoder revolution: 16 bits ≡ 65536 increments/revolution

%LW

Sign bit

Number of revolutions: 9 bits ≡ ±512 revolutions

Resolution of an encoder revolution: 22 bits ≡ 4194304 increments/revolution

%LW