Scenario
In a mechanical press, drive motors power the main drive system. Flywheels then store this energy and provide it to the rest of the machine. Clutches move the torque produced by the drive and flywheel to the gear shaft. The brakes activate when the clutch is released, slowing and / or stopping the other components.
Issue
When controlling a press flywheel to reach the target speed and then operating the clutch, the 3G3MX2 can experience a overvoltage or overcurrent event. The image below shows the clutch being activated at the first vertical cursor, where the VSD output current increases within 200ms, resulting in an overcurrent event at the second cursor.
Solution
Additional Info
Depending on the CX-Drive trace and VSD behaviour, also consider disabling the following parameters which are enabled by default, as these auto-regulate the VSD behaviour:
- A044 (Automatic Torque Boost)
- B021 (Overload Limit 1), B024 (Overload Limit 2)
- B027 (Overcurrent Suppression)
Also refer to the Troubleshooting recommendations for VSD error codes as per user manual.
The following solution is the most common in this application use case, where the manual troubleshooting recommendations do not resolve the issue.
The following will smooth the reaction on the clutch engaging, when in Sensorless Vector mode (A044 = 03).
Reduce both incrementally:
• H005 = MX2 Speed response
• B041-B044 = Torque Limit Quadrants. This effectively current limits the drive in a specific quadrant.
