YASKAWA V1000 Quick Start Manual page 157

5. When PM motors are used, the following must be considered:
Even if the HWBB function is active, although unlikely a failure in two of the drives power devices can
occur which means that current flows through the motor winding. In an induction motor no torque can
be produced by that. However, if this happens and a PM motor is connected a torque is produced
causing an alignment of the rotor magnets. The rotor may turn up to 180 deg electrically. It must be
ensured, that this possible failure mode is not safety critical for the application.
6. The time from opening the the Safe Disable input until the drive output is switched off is less than 1 ms.
YASKAWA ELECTRIC TOEP C710606 14A YASKAWA AC Drive - V1000 Quick Start Guide
8.3 Safe Disable Input Precautions
8
157