Siemens SIPART PS2 PA 6DR55 Series, Руководство по эксплуатации

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Glossary
SIPART PS2 with PROFIBUS communication
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Operating Instructions, 09/2007, A5E00127926-07
Configuration
See parameterization.
Cornerstone
Management software for process instrumentation.
Dangerous failure
Failure with the potential to switch a safety-instrumented system to a hazardous or non-
functioning safety status.
Dangerous failure
Failure with the potential to bring the safety-instrumented system into a dangerous or non-
functional status.
Decrement
From the Latin word decrementare, decrease. Decrement is the defined amount of change
when decreasing a variable(s) gradually. In informatics, it is referred to as the stepwise
decrease in a numeric value.→Increment.
Degree of protection
The degree of protection of a device indicates the extent of protection. The extent of
protection includes the safety of persons against coming in contact with live or rotating parts,
and the protection of electric resources against the penetration of water, foreign bodies and
dust. The degrees of protection of electric machines are indicated by an abbreviation
comprising two letters and two numbers (e.g. IP55). The degree of protection is coded using
the IP code. The degrees of protection are standardized in DIN EN 60529.
Device category 1
Category 1 devices must be procured such that they ensure an extremely high degree of
safety. Devices in this category must ensure an extremely high degree of safety even for
faults that occur rarely. Even if two faults occur in the device, it should not lead to ignition.
Devices in this category are suitable for use in zone 0.
Device category 2
Category 2 devices must be procured such that they ensure a high degree of safety. Devices
in this category must ensure the required degree of safety in case of frequent faults or the
ones that are normally expected, e.g. defects in the device, and prevent the ignition sources.
Devices in this category are suitable for use in zone 1.