Promac 378VLB User Manual page 9

3. Speed Adjustment
3-1 1. Open the pulley case and 1 the belt tension lock
handle.
2. Choose speed for drilling operation and move belt to
correct position for desired speed.
3. Push motor backward unitl moderate belt tension is
acquired. Then retighten the lock handle again.
Fig 16
The proper drill speed fo r a given drill bit size is as on following table:
9
Fig.16