Siemens SITRANS P500, Руководство по эксплуатации, Страница: 231 / 238

SITRANS P500 with HART
Operating Instructions, 12/2014, A5E02344528-09
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Glossary
ATEX
ATEX is an abbreviation of the French term "Atmosphère explosible" (potentially explosive
atmosphere). ATEX stands for both EC directives in the area of explosion protection: ATEX
product directive 94/9/EC and ATEX operating directive 1999/92/EC.
Auxiliary power supply
Auxiliary power supply refers to an electrical supply or reference voltage which some
electrical circuits require apart from the standard supply. The auxiliary power supply can, for
example, be specially stabilized, have a particular level or polarity and/or other properties
which are important for the correct functioning of switch components.
Auxiliary voltage
→ Auxiliary power supply
Dangerous failure
Failure with the potential to switch a safety-instrumented system to a hazardous or non-
functioning safety state.
EEPROM
EEPROM (Electrically Erasable Programmable Read-Only Memory): a non-volatile,
electronic memory module.
EEPROMs are often used where individual bytes of data (e.g. configuration data or runtime
meters) change over time and must be stored safely in the event of a mains power failure.
Failure/Fault/Error
Failure:
A resource is no longer capable of executing a required function.
Fault/Error:
Undesired state of a resource indicated by its incapability of executing a required function.
Fault/Error
→ Failure/Fault/Error