Product Name:   under current protection relay (GTT-822)

A. Scope of Application:  

 It mainly applies to 110 kV and the following various voltage levels two / three coil transformer protection
device.

B.Function and Characteristics : 

                            Protection relay Front view

                                         Protection relay Back view

C.Main Features:

 a. 4U standard aluminum chassis, combination of plug-in structure, after the plug case, each
       functional module design alone, electricity are completely separated, strong
     anti-interference ability, convenient field maintenance;
b. CPU intelligent card design, open into the open plug-ins to achieve real-time complete
    self-test; can be detected in each relay coil;
c. Plug-in based on CANBUS bus links between, reduce the connection between the
    connector plug, bad real time detection;
d. Double 32 computer systems, the redundant system; protection function using the Dezhou
    Instrument Company produced the 32 bits floating-point DSP processor, program and data
    in the chip operation; operation speed, high reliability;
e. Man-machine interface, network communication and other management functions by
   Philips Company produced 32 ARM MCU, speed, on-chip memory capacity big, strong
   ability of network interface;
f. 16 AD sampling, high measuring precision; weekly wave 48 sampling points, harmonic
   processing capability;
g. Protection module using computer assisted graphical interface design is convenient for the
   two series of products development and functional modifications, flexible, efficient
  engineering design;
h. Complete the circuit breaker control circuit is provided with a remote control, jump,
   closing, spring without stored energy blocking close function etc;
i. Use 192*64 monochrome graphic LCD, Chinese menu interface; the flexibility to choose
   double Ethernet and double 485 interface;
j. Can save at least 500 report recent incidents and operation report;
k. User management module using real-time multitask operating system, network interface,
    tasks such as real-time;
l . Can store 10 sets of protection setting value, double value zone self-test and mutual
     combination, setting change safely and convenient.
m. Based on electric power industry standard DL / T667-1999 (IEC 60870-5-103) standard

    communication protocol, and convenient with microcomputer monitoring or protect
      management computer network communication.

D.Rated Data:

     Rated AC voltage: 220V (110V orders indicate) allowable deviation +15%,-20%
a.  Rated AC data: phase voltage 100√ 3 V
     Zero-sequence voltage 100V
    AC current 5A (1A orders indicate)
    Rated frequency 50Hz (60Hz orders indicate)
b. Thermal Stability:
    AC voltage circuit: long time operation 1.4Un
    AC current circuit: long time operation  2In
                                                         10s       20In
                                                           1s         40In

                           Our products advantages

Function Introduction

The main function includes protection, data collection, controlling, communication, 

debugging and security.

The device is applied to sub computer workstation function designed. 

It can not only be used separately as digital protection device, but also form systems 

with different structures.

Protection Principle

1)Over-current section I Protection

                       Over-current section I principle diagram

2) Over-current section II Protection

                        The principle of signal similar with Picture 

3) Over-current section III Protection (Inverse time limited)  

4)Overload

                                           Overload Schematic Diagram

5) Non-electricity Protection 

6) Zero-sequence current Protection

                                        Zero-sequence current Schematic Diagram

7) Low Voltage Protection

                                           Low voltage protection principle diagram

8) TV Disconnection Test

9) Control Circuit Abnormity Alarm

10) Device Fault Alarm 

11) Telemetry, Remote Signal, Remote Control Function 

12) Wave Recorder 

 13) GPS Time Synchronization

                                                     Factory pictures