Danfoss VLT AutomationDrive FC 300 Instruction Manual

Abbreviations related to Functional Safety
Abbreviation Reference Description
Cat. EN 954-1 Safety category, levels 1-4
FIT Failure In Time: 1E-9 hours
HFT IEC 61508 Hardware Fault Tolerance: HFT = n means, that n+1 faults could cause a loss of the safety function
MTTFd EN ISO 13849-1 Mean Time To dangerous Failure: (The total number of life units) / (the number of dangerous,
undetected failures), during particular measurement interval under stated conditions
PFHd IEC 61508 Probability of Dangerous Failures per Hour. This value shall be considered if the safety device is
operated in high demand (more often than once per year) or continuous mode of operation, where
the frequency of demands for operation made on a safety-related system is greater than one per
year or greater than twice the frequency of testing.
PL EN ISO 13849-1 Performance Level: Corresponds SIL, Levels a-e
SFF IEC 61508 Safe Failure Fraction [%]; Percentage part of safe failures and dangerous detected failures of a
safety function or a subsystem related to all failures.
SIL IEC 61508 Safety Integrity Level
STO EN 61800-5-2 Safe Torque Off
VLT
®
AutomationDrive FC 300 Instruction
Manual
2 Safety Instructions and General Warning
MG.33.AG.22 - VLT
®
is a registered Danfoss trademark 2-5
2

Danfoss VLT AutomationDrive FC 300 Specifications

General

Brand	Danfoss
Model	VLT AutomationDrive FC 300
Category	DC Drives
Language	English