Automatic Encoder Adjustment - Siemens SINAMICS S120 Function Manual

Operating Modes
Vector control
3.2.12

Automatic encoder adjustment

Description
The rotor-oriented closed-loop control of the synchronous motor requires informa-
tion on the rotor angular displacement. Automatic encoder adjustment must be
used when the rotor position encoders are not adjusted mechanically and after the
motor encoder has been replaced.
Automatic encoder adjustment requires encoders with absolute position identifica-
tion. The following encoders are supported:
S Encoder with C/D track
S Resolver
S Absolute value encoder (e.g. EnDat)
S Incremental encoder with zero mark
Encoder adjustment via zero mark
if an incremental encoder with a zero mark is used, the position of the zero mark
can be compared once it has been passed. Commutation with the zero mark is
activated via p0404.15.
Commissioning
Automatic encoder adjustment is activated with p1990 = 1. The measurement is
performed the next time a pulse is enabled and the angle difference determined
(p1984) is entered in p0431. When p1990 = 2, the angle difference determined
(p1984) is not entered in p0431 and does not affect motor control. This function
can be used to check the angle difference entered in p0431.
Warning
!
The measurement causes the motor to rotate. The motor completes at least one
full revolution.
Integration
Automatic encoder adjustment is integrated in the system as follows:
Overview of key parameters:
S p0404.15
S p0431
S p1990
3-140
Commutation with zero mark
Commutation angle offset
Encoder adjustment selection
© Siemens AG, 2005. All rights reserved
SINAMICS S120 Function Manual, 06/05 Edition