1. Description

CSR**0 is a self-powered protection relay based on a microprocessor environment and working for *0kV ring main unit. It is mainly designed to protect overhead line, cable line, busbar, electromotor, transformer, etc.

 

2. Technical Feature 

●Three-phase overcurrent protection with definite-time. 

 

●Overcurrent protection with inverse-time. 

It can provide two different kinds of inverse-time curve, which have the options of tripping output or releasing alarm signal.

 

●Overload protection with definite-time 

It can provide the options of tripping output or releasing alarm signal. 

 

●Three-section zero-sequence current protection with definite time

3 section zero-sequence protections can choose tripping output or alarm signal releasing. 

 

●3 digital input

CSR**0 DI not only can connect with the auxiliary contact for ciurcuit-breaker, earthing switch, etc, but also can be the input interface for transformer protection. When it is used as transformer protection device, it can trip or alarm after the transformer protection’s contact inputs change the status. Meanwhile, it can not only connect to the high temperature contact or over temperature contact of the dry transformer, but also can connect to the light gas contact, heavy gas contact and temperature relay contact of the oil immersed transformer. 

 

●Battery with high capacity

If the device trips and CT can’t provide power for CSR**0, CSR**0 can still do some work, which it is convenient for maintenance man to check on site. 

 

●Fault indication and record

The high capacity of NVSRAM is equipped inside CSR**0, which can maximum to record **0 fault messages including time and current value with first-in first-out sequence.

 

●Communication 

RS**5 communication interface with high-speed optoelectronic isolating is equipped in CSR**0. It uses Modbus communication protocol, which can send out all messages via communication network. 

 

●Adopting technology of getting power from current transformer

If any phase current is over *0% value of the rated current, the device can still work as well as normal and provide power for circuit-breaker tripping.

 

●CSR**0 uses single chip system, its CPU contains the parts of microprocessor-based protection, such as FLASH ROM,RAM, EEPROM, A/D converter, timer, serial port, etc. Due to all connections with the external device is implemented by I/O ports and use various measures for isolation, so CSR**0 can with fewer components, work more stably and with strong anti-interference ability.

 

●User friendly design

CSR**0 adopts engineering plastics structure with one-step technology, and its enclosure design is very simple & rationalization, what is more, its depth & height are just *0mm which is tiny and space-saving for installation. On the other hand, it has large LCD and utility menu operation, which is very conveniently for users to operate.