Siemens SINAMICS S120 Function Manual page 109

Warning
!
With non-braked motors above the specified current, the measurement can cause
the motor to rotate or move.
The degree of movement depends on the specified current intensity and the
moment of inertia of the motor and load.
Notes regarding pole position identification
The relevant technique can be selected using parameter P1980. The following
techniques are available for a pole position identification routine:
S Saturation-based 1st+ 2nd harmonics (p1980 = 0)
S Saturation-based 1st harmonics (p1980 = 1)
S Saturation-based, two-stage (p1980 = 4)
S Saturation-based (p1980 = 10)
The following limitations/constraints apply for the saturation-based motion
technique:
S This technique can be used for both braked and non-braked motors.
S It can only be used for a speed setpoint = 0 or from standstill.
S The specified current magnitudes (p0325, p0329) must be sufficient to provide
a significant measuring result.
S For motors without iron, the pole position cannot be identified using the
saturation-based technique.
S For 1FN3 motors, no traversing with the 2nd harmonic should take place
(p1980 = 0, 4).
S With 1FK7 motors, two-stage procedures must not be used (p1980 = 4). The
value in p0329, which is set automatically, must not be reduced.
For the motion-based technique, the following constraints apply:
S The motor must be free to move and it may not be subject to external forces
(no hanging/suspended axes)
S It can only be used for a speed setpoint = 0 or from standstill.
S If there is a motor brake, then this must be open (p1215 = 2).
S The specified current magnitude (p1993) must move the motor by a sufficient
amount.
© Siemens AG 2006 All Rights Reserved
SINAMICS S120 Function Manual, 03/2006 Edition
Operating Modes
Servo control
3-109