VSD Sequential Starting and Linked Speed References
A Leader-Follower (Master/Slave) application is where two or more drives are electronically synchronised (Cascade Control). Typically, the first drive is configured as the “Leader” or “Master” and the subsequent drive/s that follow the master are referred to as the “Slaves” or “Followers”.
To use one VSDs Running Frequency (VSD 1 = Leader VSD) as a reference point to specify another VSDs Running Frequency (VSD 2 = Follower VSD), but also to set the Follower VSD to run at 80% of the speed of the Leader VSD, please connect the VSDs and set the required parameters as follows:
Connections:
- Connect Leader VSD AO1 with Follower VSD AI1
- Connect Leader VSD GND with Follower VSD GND
*Please use shielded cable to prevent electromagnetic interference by other appliances on the analog signal sent to the VSD. For EMC Mitigation: 1) Allow for at least 20cm distance between communication cables and motor wires. 2) Do not use the same cable tray. 3) Insert wires in metal pipes if possible.
Parameter Settings:
- VSD 1 (Leader): Set B6-05 = 0.8 (Set AO1 Gain = 80%)
- VSD 2 (Follower): Set B0-03 = 2 (Set main Frequency source = AI1)
For more information regarding the use of VSDs for Leader-Follower applications, please our blog entry HERE.
