Siemens SINAMICS S120 Function Manual page 786

Applications
12.5 Description
Procedure for star-delta changeover
1. Start condition:
For synchronous motors, the actual speed must be lower than the star field-weakening
speed. This prevents the regenerative voltage from exceeding the terminal voltage.
2. Pulse inhibit:
The pulses are suppressed after the changeover speed (p2155) is reached.
3. Open the motor contactor:
Motor contactor 1 is opened (r0830 = 0) and the status bit "Motor data set changeover
active" (r0835.0) is set.
4. Change over the drive data set:
The requested data set is activated (r0051 = requested data set).
5. Energize the motor contactor:
After the feedback signal (motor contactor opened) for motor contactor 1, the appropriate
bit of r0830 is set and motor contactor 2 is energized.
6. Enable the pulses:
After the feedback signal (motor contactor closed) for motor contactor 2, the bit "motor
changeover active" (r0835.0) is reset and the pulses are enabled. The changeover is
complete.
Function diagrams (see SINAMICS S120/S150 List Manual)
• 8565
• 8570
• 8575
786
Data sets - Drive Data Sets (DDS)
Data sets - Encoder Data Sets (EDS)
Data sets - Motor Data Sets (MDS)
Function Manual, (FH1), 04/2014, 6SL3097-4AB00-0BP4
Drive functions