fastline12
Aerospace
- Jan 27, 2011
- 306
Due to a drive failure today, we are installing a replacement A500 VFD. We planned to review this application more before attempting but hand is being forced due to down time.
The installation is very straight forward but this machine orients the spindle for a tool change by commanding a low rpm (approx 40rpm)while pushing a shot pin at a collar with a slot in it to lock the spindle in place. The way it was designed, when the pin falls in, there is an immediate signal to the drive to halt operation. However, the previous drive was a V/Hz drive with no knowledge of rpm. The new drive will be operated in sensorless vector mode and the concern is if the drive can out power this locking mechanism and damage it if signal to stop is not received very promtly.
Obviously there is too much being left out here to really say but I am more or less asking if other machines are doing something similar successfully with a sensorless system? Or even encoder feeback system. maybe the sensorless system in the A500 is slow enough to react to the stop? The motor would be spinning fast enough to develop full torque at these speeds.
The installation is very straight forward but this machine orients the spindle for a tool change by commanding a low rpm (approx 40rpm)while pushing a shot pin at a collar with a slot in it to lock the spindle in place. The way it was designed, when the pin falls in, there is an immediate signal to the drive to halt operation. However, the previous drive was a V/Hz drive with no knowledge of rpm. The new drive will be operated in sensorless vector mode and the concern is if the drive can out power this locking mechanism and damage it if signal to stop is not received very promtly.
Obviously there is too much being left out here to really say but I am more or less asking if other machines are doing something similar successfully with a sensorless system? Or even encoder feeback system. maybe the sensorless system in the A500 is slow enough to react to the stop? The motor would be spinning fast enough to develop full torque at these speeds.