Siemens 6DR50 Series Operating Instructions Manual page 284

Glossary
Configuring
See parameter assignment.
Control fitting
A valve consisting of an actuator + control valve + positioner.
Cornerstone
Management software for process instrumentation.
Decrement
From the Latin word decrementare, decrease. Decrement is the defined amount of change
when decreasing a variable(s) gradually. IT term that refers to a step-by-step 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 or 20.
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 ones
that can be normally expected, e.g. defects in the device, and avoid ignition sources.
Devices in this category are suitable for use in zone 1 or 21.
Device category 3
Category 3 devices must be procured such that they ensure a normal degree of safety.
Devices in this category must ensure the required degree of safety in case of frequent faults
or ones that can be normally expected, e.g. defects in the device, and avoid ignition sources.
Devices in this category are suitable for use in zone 2 or 22.
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SIPART PS2 with and without HART
Operating Instructions, 09/2014, A5E00074631-12