Siemens SITRANS P Operating Instructions Manual page 274

Glossary
Fingerprint
Numerical value generated by the device when you start safety validation via the "Functional
Safety" wizard. By comparing the fingerprint, you determine whether or not the device and the
safety-related parameters have changed erroneously during activation of the functional safety.
Firmware
Firmware (FW) is software that is embedded on a chip in electronic devices – in contrast to
software which is saved on hard disks, CD-ROMs or other media. These days, firmware is
mostly stored in a flash memory or EEPROM.
Firmware usually contains the elementary functions for controlling the device, as well as input
and output routines.
Frequency shift keying
Frequency shift keying is a simple form of modulation, where the digital values 0 and 1
modulate the actual current signal by means of two different frequencies.
Frequency Shift Keying (FSK)
Frequency shift keying
→
HART
HART (Highway Addressable Remote Transducer) is a standardized, widely used
communications system used to structure industrial fieldbusses. The communications system
provides digital communications for multiple participants (field devices) via a common databus.
HART is based especially on the equally widely used 4/20 mA standard for the transfer of
analog sensor signals. The cabling from existing older systems can be used directly and both
systems operated in parallel.
HART specifies several protocol levels in the OSI model. It facilitates the transfer of process
and diagnostics data and control signals between field devices and high-level control systems.
Standardized parameter sets can be used for the manufacture-independent operation of all
HART devices.
Typical applications include transmitters for measuring mechanical and electrical dimensions.
Non-volatile memory
EEPROM
→
r
Spread
→
Risk
Combination of the probability of damage occurring and the extent of the damage.
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SITRANS P320/P420 with 4 to 20 mA/HART
Operating Instructions, 11/2019, A5E44852162-AC