The PRS-778 is a numerical distributed transformer protection intended
for protecting and monitoring various transformers of various voltage
level, ranging from 1000kV to 110kV. PRS-778 can detect and clear all
types of internal faults.PRS-778 provides fast and selective protection,
monitoring and control for two and three-winding transformers,
autotransformers, step-up transformers and generator-transformer block
units, phase shifting transformers, special railway transformers, shunt
reactors, etc. The relay can operate correctly over a wide frequency
range in order to accommodate power system frequency variations during
disturbances and generator start-up and shut-down.This relay can sample
the analog values from the traditional instrument transformers, or
receive the sampled values from the electronic current and voltage
transformers (via a merging unit). The binary inputs and outputs of this
relay can be configured according to the demands of a practical
engineering through the PRS IED Studio configuration tool auxiliary
software, which can meet some special requirements of protection and
control functions.This relay can fully support the IEC61850
communication protocol and GOOSE function, and can completely meet the
demands of a modern digitalized substation.
01
This device is based on a 32-bit high performance dual-core processor, internal high speed bus and intelligent I/O ports, and the hardware is in modularized design and can be configured flexibly, featuring interchangeability and easy extension and maintenance.
02
Modularized hardware design makes this relay be easily upgraded or repaired by a qualified service person. Various function optional modules can satisfy various situations according to the different requirements of the users..
03
The adoption of 16-bit A/D converter and the dual-channel sampling technology can ensure the accuracy and reliability of protection sampling and the correctness of protection operation. It also provides dedicated current transformers for metering, and ensures the high accuracy of telemetering with 48-point high speed sampling rate per cycle.
04
This device can sample the analog values from the traditional instrument transformers, or receive the sampled values from the electronic transformers. It can support the protocol IEC60044-8, IEC61850-9-2 and GOOSE.
05
Various algorithms for protection and measurement have been completed in this device for the feature of electronic transformer sampling, such as the error prevention method of multi-algorithms data anomaly for the digital channels, to realize high accuracy and reliability under various conditions of network faults or communication interruption.
06
This device has powerful GOOSE functions, and the connection and cooperation between some devices can be realized without using electrical cables, to facilitate the realization of such functions as simple bus differential protection, overload interlock shedding function and backup automatic transfer function etc.
07
This device has fully realized the technology to integrate six functions into one device: protection, measurement, control, remote signaling, merging unit function and remote module functions, to improve the reliability.
08
Various methods of GPS time synchronization are supported in this relay, including SNTP, pulse per second (PPS) and IRIG-B synchronization.
09
The protection modules are completely separated from other modules, and are independent in both hardware and software. The protection functions do not depend on the communication network, so the failure of communication network will not affect the normal operation of the protection functions.
010
Mature protection configuration, fast speed and high security performance can meet the practical requirements. Each protective element is independent, so it is very convenient for whether adopting the selected protective element.
011
This device constantly measures and calculates a large amount of analog quantities, such as phase voltage, phase-to-phase voltage, neutral voltage, phase current, neutral current, active power, reactive power, power factor and frequency etc.
012
The human machine interface (HMI) with a small control module (a 240×128-dot LCD, a 9-key keypad and 19 LED indicators) on the front panel is very friendly and convenient to the user.
013
This device can communicate with a SAS or RTU via different communication intermediates: thernet network, RS-485 serial ports. The communication protocol of this device is optional: IEC61850, IEC60870-5-103, DNP3.0 or ModBus.
014
This device can detect the tripping circuit of the circuit breaker and monitor the operation (close or trip) time of a circuit breaker by checking the auxiliary contacts of the circuit breaker.
015
Complete event recording function is provided: 512 latest protection operation reports, 512 latest supervision records, 128 latest control operation records, 128 latest user operation records and 2000latest records of time tagged sequence of event (SOE) can be recorded.
016
Powerful fault and disturbance recording function is supported: 64 latest fault or disturbance waves, the duration of a wave recording is configurable.
