Microprocessor Numerical Relay Protection Device | IEC 60255 | For Transformer Feeder Line 10kV/35kV Substation

Flexible combination of voltage and current output It provides standard 4-phase voltage and 3-phase current output and allows convenient combinations of outputs for various protection test types. Each phase can output 120 V, and the current in three phases can reach 120 A. For the fourth phase, the voltage Ux is a multifunctional setting that can be set to one of four 3U0 voltages or any arbitrary voltage value, and it will output accordingly.

Single-player operation is convenient. The device panel includes a trackball mouse, an optimized keyboard, and a large TFT LCD display; it features built-in Chinese Windows operating software. You can start using it right after turning it on—the operation is convenient and quick.

Two operating modes Besides standalone operation, the device can connect to a laptop or desktop computer for control; both methods offer identical functionality—truly complete dual operating modes.

U new high‑fidelity linear amplifier The output stage consistently employs high‑fidelity, highly reliable modular linear amplifiers rather than switching amplifiers, delivering outstanding performance. It will not cause high-frequency or medium-frequency interference at the test site, and it ensures smooth waveforms throughout the entire current range, from large currents to very small currents, with excellent precision.

High-performance host The output section uses DSP control for fast processing, strong real-time digital signal processing capability, wide transmission bandwidth, and high-resolution D/A conversion control. High waveform accuracy output, low distortion, good linearity. It incorporates a large number of advanced technologies and precision component materials, along with professional structural design, resulting in a small size, low weight, comprehensive functionality, and convenient portability. It works immediately upon power-on, and flow testing is very convenient.

The software is powerful. Capable of performing large, complex verification tasks with high levels of automation, including conveniently testing and scanning various protection settings, fault playback, real-time storage of test data, display of vector graphics, online report printing, and more.

It has an independent dedicated DC power output. Device type includes one line of adjustable DC power output at 110 V and 220 V.

The interface is complete. The device panel includes a built-in keyboard and mouse for single-unit operation, and it can also connect external keyboards and mice via keyboard and mouse ports for operation; it also has two USB ports and an RS232 port, allowing communication with computers and other external devices.

Well-developed self-protection features The cooling structure design is reasonable, hardware protection measures are reliable and comprehensive, it features soft power startup functionality, and the software performs self-diagnostics for faults and provides functions such as lock output.

Lightweight small-to-medium integrated single unit and an integrated structure It incorporates a large amount of high-tech, carefully designed ultra-light, compact structure, making the entire device extremely small and lightweight.

Rated parameters

Hardware components of the device

High-performance industrial control computer

This device uses a high‑performance industrial PC as the control unit for the embedded system and runs the Windows operating system directly. The device panel features a 6.4″ true‑color TFT LCD display, a trackball, and an optimized keyboard; you can use it directly without needing an external mouse or keyboard. The device back panel includes a USB port, a 10–100 Mbps Ethernet port, a serial communication port, and more, making it convenient to transfer data, communicate data, and perform software updates.

The entire testing process and results are displayed on the LCD screen; the complete Chinese-language user interface is clear, bright, intuitive, and convenient. Operation control is achieved using a joystick and a panel keyboard. It’s simple and convenient to operate; basic computer knowledge is sufficient, and it’s very easy to master.

Digital Signal Processor Microcomputer

The device uses a high-speed digital control processor as its output core, employing 32-bit double-precision algorithms in software to generate arbitrarily precise waveforms for each phase. Due to the integrated structure, parts are tightly combined, the data transmission distance is short, and the design is compact. It overcame the issue of fewer waveform points in the output due to long data communication lines and a narrow bandwidth when controlling a laptop-based test instrument directly.

Analog-to-digital conversion and low-pass filtering

Utilizes a high-precision D/A converter to ensure precision and linearity across the entire range of current and voltage.

Due to a high density of fitting points, high waveform fidelity, small harmonic components, and low demands on low-pass filters, it exhibits excellent transient characteristics, phase characteristics, and frequency response characteristics; precise phase shifting and harmonic superposition are easy to achieve, and high precision can also be maintained at high frequencies.

Voltage and current amplifier

Current and voltage consistently employ a high‑performance linear amplifier output method, enabling current and voltage sources to directly output waveforms ranging from DC to signals containing various frequencies, such as square waves and composite waveforms combining harmonics at different orders, fault transient waveforms, etc., while providing clean, smooth outputs that do not cause high‑frequency radiation interference for nearby equipment. It can effectively simulate current and voltage characteristics during short‑circuit faults.

The amplifier circuit employs imported high‑power, high‑fidelity modular power devices as the output stage, combined with a carefully designed cooling structure that provides sufficient power redundancy and thermal capacity. The amplifier circuit includes comprehensive protection against overheating, overcurrent, overvoltage, and short circuits. When an overcurrent condition occurs in the current circuit, or an overload or short circuit occurs in the voltage circuit, the output power is automatically limited, the entire amplifier circuit is shut down, and an alarm signal is displayed. To prevent overheating of the amplifier circuit during long operation at high currents, the device has implemented software time limits for high current conditions. When outputting 10A or less, the device can operate continuously. When current exceeds 10A, the software initiates a timed operation. Once the time limit expires, the software automatically shuts off power output and provides an alarm indicator. The higher the output current, the shorter the time limit.

Opening/closing quantity

The device has 8 input channels and 4 output channels.

The switch input circuit is compatible with open contacts and 0–250 V potentiometers. In voltage mode, 0–6 V is ON, and 11–250 V is OFF. Switch quantity allows convenient measurement of the switching time of each phase switches and the difference in switching times.

The input section is isolated from the main unit’s power supply and amplifier power supplies, etc. Since it’s a floating topology upon entry, the input side’s public terminals are not connected to current/voltage public terminals like UN, IN, etc.

The analog input has a polarity; connect the positive side to the common terminal and the negative side to the input terminal, ensuring that the voltage at the common terminal is higher than at the input terminal. During field wiring, connect the positive end to the public terminal block labeled “+KM," and connect the negative end to the terminal block. If connected incorrectly, it will not detect correctly.

The output from the relay's open contact is partially activated. Output capacity: DC 220 V / 0.2 A; AC 220 V / 0.5 A. The switch output is fully isolated from voltage, current, switching status, etc. The steps for opening each quantity vary across different test modules. For detailed instructions, please refer to the software operation guides for each module.