Application Scope - Siemens SIPROTEC 4 Manual

Introduction

1.2 Application Scope

1.2 Application Scope
The digital voltage and frequency protection SIPROTEC 4 7RW80 is a versatile device designed for protection,
control, and monitoring of transformers, electrical machines and distribution systems.
The device can be used for
•
System decoupling or for load shedding if ever there is a risk of a system collapse as a result of inadmis-
sibly large frequency drops
•
Monitoring voltage and frequency thresholds
Voltage, frequency and overexcitation protection can be used to protect generators and transformers in the
event of
•
Defective voltage control or defective frequency control
•
Full load rejection
•
Islanding generation systems.
Protection Functions
Multilevel voltage and frequency protection is the basic function of the device.
Further protection functions included are load restoration, synchrocheck, overexcitation protection, vector
jump and flexible protective functions.
Control Functions
The device provides a control function which can be accomplished for activating and deactivating the switch-
gear via operator buttons, port B, binary inputs and - using a PC and the DIGSI software - via the front inter-
face.
The status of the primary equipment can be transmitted to the device via auxiliary contacts connected to
binary inputs. The present status (or position) of the primary equipment can be displayed on the device, and
used for interlocking or alarm condition monitoring. The number of operating equipments to be switched is
limited by the binary inputs and outputs available in the device or the binary inputs and outputs allocated for
the switch position indications. Depending on the primary equipment being controlled, one binary input
(single point indication) or two binary inputs (double point indication) may be used for this process.
The capability of switching primary equipment can be restricted by a setting associated with switching
authority (Remote or Local), and by the operating mode (interlocked/non-interlocked, with or without pass-
word request).
Processing of interlocking conditions for switching (e.g. switchgear interlocking) can be established with the
aid of integrated, user-configurable logic functions.
Messages and Measured Values; Recording of Event and Fault Data
The operational indications provide information about conditions in the power system and the device. Meas-
urement quantities and values that are calculated can be displayed locally and communicated via the serial
interfaces.
Device messages can be assigned to a number of LEDs on the front cover (allocatable), can be externally
processed via output contacts (allocatable), linked with user-definable logic functions and/or issued via serial
interfaces.
During a fault (system fault) important events and changes in conditions are saved in fault protocols (Event
Log or Trip Log). Instantaneous fault values are also saved in the device and may be analyzed subsequently.
Communication
The following interfaces are available for communication with external operating, control and memory
systems.
The USB DIGSI interface on the front cover serves for local communication with a PC. By means of the
SIPROTEC 4 operating software DIGSI, all operational and evaluation tasks can be executed via this operator
interface, such as specifying and modifying configuration parameters and settings, configuring user-specific
18 SIPROTEC 4, 7RW80, Manual
C53000-G1140-C233-4, Edition 07.2018