SELV
Safety extra low voltage (SELV) is voltage < 30 V AC / 60 V DC that is generated by means
of safety transformer, accumulator etc.
SIMATIC PDM
SIMATIC PDM (Process Device Manager) is an integrated, vendor-neutral tool used for
configuring, parameter assignment, commissioning and diagnosing intelligent process
devices.
SIMATIC PDM makes it possible to configure a large variety of process devices with
a single software on a standardized user interface.
Terminating resistor
A terminating resistor is a resistor that terminates the data transmission line to avoid
reflections.
Time synchronization
Time synchronization ensures that all clocks run synchronously. A master clock distributes the
time in a configurable cycle to all other components in the automation system that have a clock.
The components use this distributed time to set their own clocks.
TN-S system
In a TN-S system, the neutral conductor (N) and protective conductor (PE) are routed
separately from each other. The neutral conductor is connected to the grounded protective
conductor at a central point, and only there. The conductor can be grounded any number of
times.
Token
In network technology a token refers to a bit pattern that is passed from one bus node to
another, enabling that node to access the bus.
Transmission speed
The transmission speed specifies the number of bits transmitted per second.
Type of ignition protection
The special measures applied to electrical equipment to prevent the ignition of an ambient
potentially explosive atmosphere.
Ungrounded
Having no conductive connection to ground
Glossary
Compact FF Link
Operating Instructions, 03/2015, A5E35651552-AA
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