ABB SensyTemp TSA101, Safety Instructions

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Field of Application
4 SensyTemp TSP SM/TSP/SIL-EN
1 Field of Application
Temperature monitoring of solids, fluids and gases of all types in containers and pipes
according to the special safety engineering requirements of IEC 61508.
The operating limits are defined in the data sheets and operating instructions for the separate
models. In case of questions, please contact your ABB partner.
2 Acronyms and abbreviations
Acronym /
Abbreviation
Designation Description
HFT Hardware Fault
Tolerance
The hardware fault tolerance of the device.
This is the capability of a functional unit to continue the
execution of the demanded function in case of faults or
deviations.
MTBF Mean Time
Between Failures
This is the mean time period between two failures.
MTTR Mean Time To
Repair This is the mean time period between the occurrence of
a failure in a device or system and its repair.
PFD Probability of
Failure on
Demand
This is the likelihood of dangerous safety function
failures occurring on demand.
PFD
AVG
Average
Probability of
Failure on
Demand
This is the average likelihood of dangerous safety
function failures occurring on demand.
SIL Safety Integrity
Level
The international standard IEC 61508 specifies four
discrete safety integrity levels (SIL 1 to SIL 4). Each
level corresponds to a specific probability range
regarding the failure of a safety function. The higher the
safety integrity level of the safety-related systems, the
lower likelihood of non-execution of the demanded
safety functions.
SFF Safe Failure
Fraction
The fraction of non-hazardous failures, i.e. the fraction of
failures without the potential to set the safety-related
system to a dangerous or impermissible state.
Low demand
mode Low demand
mode of
operation Measuring mode with low demand rate. Measuring
mode, in which the demand rate for the safety-related
system is not more than once a year and is not greater
than double the frequency of the periodic test.
DCS Distributed
Control System
Control systems that are used in industrial engineering
applications to monitor and control distributed
equipment.