Abbreviation Long form Meaning
NAMUR Standards working group for meas‐
urement and control technology in the
chemicals industry
Association of users in process conductor technology
µC Microcontroller One-Chip computer system
NCS Non-Contacting Sensor Sensor for non-contacting position detection
NEMA National Electrical Manufacturers As‐
sociation
US standards institution
National Electrical Manufacturers Association
NPT National Pipe Thread Taper Pipe threading for self-sealing threads as per ANSI B.1.20.1
OPOS interface
®
Open Positioner Interface Standard interface for the connection between a positioner and
a pneumatic linear or part-turn actuator
PA Process Automation Process automation
PDM Process Device Manager Siemens communication software / Engineering tool
PROFIBUS Process Field Bus Fieldbus
RSS feed Rich Site Summary Feed Shows changes in regular intervals to web sites you are sub‐
scribed to.
VDE Verband der Elektrotechnik, Elektro‐
nik und Informationstechnik e. V.
Industrial and professional association
VDI Verein Deutscher Ingenieure e. V. Technical/scientific association
G.2 Abbreviations for functional safety
Abbreviation Full term in English Meaning
FIT Failure in Time Frequency of failure
Number of faults within 10
9
hours
HFT Hardware Fault Tolerance Hardware fault tolerance:
Capability of a function unit to continue executing a required
function in the presence of faults or deviations.
MooN "M out of N" voting Classification and description of the safety-instrumented system
in terms of redundancy and the selection procedures used.
A safety-instrumented system or part that consists of "N" inde‐
pendent channels. The channels are connected to each other in
such a way that "M" channels are in each case sufficient for the
device to perform the safety instrumented function.
Example:
Pressure measurement: 1oo2 architecture. A safety-instrumen‐
ted system decides that a specified pressure limit has been ex‐
ceeded if one out of two pressure sensors reaches this limit. In a
1oo1 architecture, there is only one pressure sensor.
MTBF Mean Time Between Failures Average period between two failures
MTTR Mean Time To Restoration Average period between the occurrence of a fault in a device or
system and restoration of functionality
PFD Probability of Dangerous Failure on
Demand
Probability of dangerous failures of a safety function on demand
PFD
AVG
Average Probability of Dangerous Fail‐
ure on Demand
Average probability of dangerous failures of a safety function on
demand
Abbreviations
G.2 Abbreviations for functional safety
SIPART PS2 with 4 to 20 mA/HART
322 Operating Instructions, 11/2019, A5E00074631-AE
To Next Page
Loading...
Need help?
General
