JVL MIS17 Series, User Manual

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JVL Industri Elektronik A/S - User Manual - Integrated Stepper Motors MIS17x, 23x, 34x, 43x 59
3.1 STO - Safe Torque Off
Example of the physical label on the motor where the S8 is identified and marked with a
red circle:
3.1.3 Abbreviations
Abbreviation Reference Description
Cat. ISO13849-1 Category, level “1-4”
DC - Diagnostic coverage
FIT - Failure in time: 1E-9/hour
HFT IEC61508 Hardware fault tolerance: HFT = n means that n+1 faults cause a loss of
the safety function.
MTTFd ISO13849-1 Mean time to failure – dangerous. Unit: Years
PFH IEC61508 Probability of dangerous failures per hour. Consider this value if the
safety device is operated in high demand or continuous mode of
operation, where the frequency of demands for operation made on a
safety-related system is greater than once per year.
PFD IEC61508 Average probability of failure on demand, value used for low demand
operation.
PL ISO13849-1 Performance level, used to specify the ability of safety-related parts of
control systems to perform a safety function under foreseeable conditions.
Levels a–e.
SIL IEC61508
IEC62061 Safety integrity level
STO IEC61800-5-2 Safe Torque Off
SRECS IEC62061 Safety related electrical control system
SRP/CS ISO13849-1 Safety related parts of control systems
PDS/SR IEC61800-5-2 Power drive system (safety related)
Option
TT2559-01GB