Siemens SIMOVERT Masterdrives SSB Operating Instructions Manual page 21

02.2000
♦ In the "safety off" status, the SSB board prevents the motor accidentally rotating .
♦ Please remember that the motor terminals might still be at hazardous potential in the "Safety Off"
state!
♦ The motor can no longer produce a torque when the "Safety Off" function is active. Drives which cannot
self-lock (e.g. vertical axes) must be immobilized by means of a mechanical brake.
♦ The "Safety Off" function is not a suitable means of decelerating a rotating motor down to standstill very
quickly since, when the gating pulses are disabled, the motor is braked solely by the connected load.
♦ For the above reason, the motor must therefore be stopped by the SIMOVERT MASTERDRIVES and then
switched to the "Safety Off" status via the SSB board. Work can then be carried out on mechanical drive
components with the line voltage connected and no electrical isolation between the motor and SIMOVERT
MASTERDRIVES converter.
♦ The "Safety Off" function complies with EN 60204-1 / DIN VDE 0113 Part 1, Section 5.4 "Devices for
Shutdown and Prevention of Accidental Starting", but not with Section 5.3 "Master Switch Function".
The "Safety Off" function is also suitable for implementing the Stop function according to categories 0 and 1
in EN 60204-1 / VDE 0133, Part 1, Section 9.2.2.
♦ The "Safety Off" function complies with the relevant product safety standards applicable for individual
machines or plants regarding protection categories for prevention of hazardous movements on the machine
or plant.
♦ The control must be designed and implemented such that the monitors and control functions for ensuring
compliance with safety standards are effective and reliable.
♦ Residual risk:
If two IGBTs are destroyed simultaneously, the drive might be aligned slightly even if the "Safety
Off" function is active.
Siemens AG 6SE7080-0AX87-1JB0
Safe Stop Board Operating Instructions
NOTES
21