Automatic Encoder Adjustment - Siemens SINAMICS S120 Function Manual

3.2.13

Automatic encoder adjustment

Description
The pole wheel-oriented closed-loop control of the synchronous motor requires
information about the pole wheel position angle. Automatic encoder adjustment
must be used if the pole wheel position encoders are not mechanically adjusted
and after a motor encoder has been replaced.
Automatic encoder adjustment only makes sense for encoders with absolute posi-
tion information and/or zero mark. The following encoders are supported:
S Encoder with C/D track
S Resolver
S Absolute encoder (e.g. EnDat, SSI)
S Incremental encoder with zero mark
Encoder adjustment using a zero mark
If an incremental encoder with zero mark is being used, after the zero mark has
been passed, the position of the zero mark can be calibrated. Commutation with
the zero mark is activated via p0404.15.
Commissioning
Automatic encoder adjustment is activated with p1990 = 1. When the pulses are
enabled the next time, the measurement is carried-out and the angular difference
determined (p1984) is entered into p0431. For p1990 = 2 the determined angular
difference (p1984) is not entered into p0431 and has not effect on the closed-loop
motor control. Using this function, the angular difference – entered into p0431 –
can be checked. For extremely high moments of inertia, the run time can be scaled
higher using p1999.
Warning
!
The measurement causes the motor to rotate. The motor turns through a minimum
of one complete revolution.
© Siemens AG 2006 All Rights Reserved
SINAMICS S120 Function Manual, 03/2006 Edition
Operating Modes
Vector control
3-155