Risk Assessment - YASKAWA E-V Series User Manual

5.2

Risk Assessment

When using the Safety Module, be sure to perform risk assessment of the servo system in advance. Make sure
that the safety level of the standards is met. For details about the standards, refer to Harmonized Standards at
the front of this manual.
The following residual risks can be present even when the safety functions operate. Therefore, safety must
always be given consideration during risk assessment.
• If external forces (such as gravitational force with a vertical axis) are applied when the safety functions of
the Safety Module are operating, the motor will rotate due to the action of these external forces. Provide a
separate mechanical brake to secure the motor.
• If the SERVOPACK fails, the motor may operate within a range of 180 electrical degrees. Make sure that
safety is ensured even in hazardous situations. 
The number of rotations and movement distance for each type of motor are listed below.
Rotational Servomotor: 1/6 rotation max. (rotation angle at motor shaft conversion)
Direct Drive Motor: 1/20 rotation max. (rotation angle at motor shaft conversion)
Linear Servomotor: 30 mm max.

5.2 Risk Assessment

5-3