Siemens SIPROTEC 5 Manual page 481

PLC
See Programmable Logic Controller
Plt (Perceptibility, long-term)
Long-term flicker strength according to IEC 61000-4-15
PMU
See Phasor Measurement Unit
PQDIF
PQDIF is a binary file format in the IEEE Standard 1159.3-2003 that is used to exchange the measured values
of current, voltage, power, energy between software applications.
PQDIF means Power Quality Data Interchange Format.
Product code
Compilation of product features in readable form
PROFIBUS
PROcess Feld BUS, German Process and Fieldbus standard (EN 50170). The standard specifies the functional,
electrical and mechanical characteristics for a bit-serial fieldbus.
PROFIBUS Address
A unique PROFIBUS address must be assigned to each SIPROTEC device within a PROFIBUS network. A total of
254 PROFIBUS addresses per PROFIBUS network are available.
Programmable Logic
The programmable logic is a function in Siemens devices or station controllers, enabling user-specific func-
tionality in the form of a program. This logic component can be programmed by various methods: CFC (=
Continuous Function Chart) is one of these. SFC (Sequential Function Chart) and ST (Structured Text) are
others.
Programmable Logic Controller
Programmable logic controllers (PLC) are electronic controllers whose function is saved as a program in the
control unit. The construction and wiring of the device do not therefore depend on the function of the control.
The programmable logic controller has the structure of a computer; it consists of CPU with memory, installa-
tion/extension groups (for example, DI, AI, CO, CR), power supply (PS) and rack (with bus system). The periph-
erals and programming language are oriented towards the circumstances of the control system.
Project
In terms of content, a project is the replication of a real energy supply system. In graphic terms, a project is
represented as a number of objects which are incorporated in a hierarchical structure. Physically, a project
consists of a series of directories and files containing project data.
Protection Device
A protection device detects fault states in distribution networks, taking into account various criteria, such as
fault distance, fault direction or fault duration, triggering a disconnection of the defective network section.
PRP
PRP is a redundancy protocol for Ethernet networks that is specified in IEC 62439-3. Unlike conventional
redundancy procedures, such as RSTP (Rapid Spanning Tree Protocol, IEEE 802.1D-2004) PRP offers uninter-
ruptible switching, which avoids any down time in the event of a fault, and thus the highest availability.
SIPROTEC 5, Fault Recorder, Manual
C53000-G5040-C018-5, Edition 11.2017
Glossary
481