1Overview
The AT-P3000 series microcomputer protection and measurement device is a new generation microcomputer based relay protection device developed by our company on the basis of digesting and absorbing advanced experience of similar products at home and abroad, based on digital processing technology.
The design of AT-P3000 series microcomputer protection and measurement device adopts object-oriented design method, taking one power interval as the basic unit, comprehensively considering protection, measurement, and monitoring functions, and cooperating with advanced fieldbus network communication method, it can achieve four remote functions of telemetry, remote signaling, remote control, and remote adjustment. This series of microcomputer protection and measurement devices includes line protection, transformer protection, motor protection, generator protection, capacitor protection, PT monitoring switching device, backup power automatic switching device, etc., providing complete monitoring and protection functions for 35kV and below plant power and substation comprehensive automation systems.
2Characteristics of serialized products
●Object oriented design philosophy：Adopting a distributed design where one component (one interval) corresponds to one device, the device integrates protection, measurement, control, remote signaling, and remote adjustment functions, and can be directly installed (or grouped) on the switchgear locally. Each interval function is independent, and each device is only connected through a network, with flexible network configuration. Any device failure only affects one component, and its reliability has been greatly improved.
●Highly reliable electromagnetic compatibility design：Adopting advanced industrial grade chips, the device adopts a dual CPU structure of digital signal processor (DSP) and microcontroller (MCU), and the hardware system has high anti-interference ability and operational reliability. The standard back inserted aluminum profile industrial chassis commonly uses multi-layer circuit boards and surface mount technology, coupled with carefully designed anti-interference components, making the device highly electromagnetic compatible.
●High sampling accuracy:Using a fast and high-resolution A/D converter, with 24 point sampling per week, combined with frequency automatic tracking technology and a specially designed measurement CT, ensures high measurement accuracy and response speed. And it can monitor the power quality, calculate and analyze the 2-15th harmonic of current and voltage in real time, and complete the calculation of active power, reactive power, power factor, etc.
●Powerful communication function and independent protection function：Adopting CAN or RS485, Modbus RTU fieldbus technology, the system has fast response speed and applies standard communication protocols to meet the requirements of automation systems; The protection function of the device is completely independent of the communication network, and network failure does not affect the normal operation of the protection.
●Standardized and modular design:Standardization of hardware design and modularization of software design not only improve the quality of software and hardware design, but also provide convenience for production, debugging, and maintenance. The protection CT and measurement CT in the device are separated, and the protection, measurement, communication, and control functions are relatively independent. The protection function does not rely on the communication network at all, and network failure does not affect the normal operation of the protection.
●Humanized and friendly human-machine interface:Adopting a large screen LCD display with a tree shaped menu structure, the trip report, alarm report, and setting value are clearly displayed on the LCD, and debugging, setting, and maintenance work can be smoothly completed without referring to the manual.
●Complete operation box functions:Retaining the independent input/output circuit and operation circuit of traditional microcomputer protection, the circuit breaker has adaptive tripping and closing current.
●Logical control function:It can achieve logical definition of input quantity and output discrimination quantity (this function is provided when requested by the user, and several output relays need to be added in hardware), and can also be used for simple operation locking control.

●Software matrix pressure plate function:The protection configuration is very flexible, and a software matrix pressure plate is introduced, which uses control words to determine the exit properties of various protection actions. This not only reduces the wiring inside the screen, but also greatly increases the adaptability of the device, making it easy to use and maintain.

3. External dimensions and opening dimensions