2 - Fagor Automation

Functional safety
9.
FUNCTIONAL SAFETY
Technical data of the safety function
326
DDS
HARDWARE
Ref.1307
320
9.6 Technical data of the safety function
Fagor Automation drives AXD/SPD only offer the safety function STO
(Safe Torque Off) defined according to the standard IEC 61800-5-2.
To calculate the Performance Level (PL of ISO 13849-1) and/or the Safety
Integrated Level (SIL of IEC 62061) use the following data referred to
AXD/SPD drives given in the following tables:
T. H9/1 Calculation data according to IEC 61508 and IEC 61800-5-2.
Lifetime years 20
SFF (Safe Failure Fraction) % 99
PFH (Average frequency of a dangerous
Failure per Hour)
1/h 1.5654E-07
HFT (Hardware Fault Tolerance) 1
SIL (Safety Integrity Level) 2
This data is calculated considering a contactor with 500,000 life cycles
and a demand from the STO safety function every 5 minutes running 24
hours a day. For higher demands, check with Fagor Automation.
T. H9/2 Calculation data according to ISO 13849-1.
PL (Performance Level) d
MTTFd (Mean Time To dangerous Failure) years 21.4
DC (Diagnostic Coverage) % 98
Category 3
CCF (Common Cause Failure) 80
Note. Bear in mind that PFH and MTTFd are calculated values and show
the probability of failure. This does not guarantee the useful life of a particular
product.
The external main contactor - KM1 installed must comply with standard
IEC 60947-4-1 (if it is a mirror-contact type) or with IEC 60947-5-1 (if its
contact is joined mechanically).
The Drive Enable has been designed to be used in high-demand mode
(more than once a year) according to standard IEC 61800-5-2.