SEL-351A Microcomputer Protection Device
LEHIY item code: LH-SEL-0010
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We offer remote or on-site installation and commissioning services for the American SEL-351A microprocessor-based protection device! The American SEL microprocessor-based protection device, also known as the SEL relay, is an electromechanical protection device.
SEL relays are a top choice for microprocessor-based protection products in substations worldwide.
We are an authorized distributor of popular American SEL microprocessor-based protection device series products, including SEL-351A, SEL-551, SEL-551A, SEL-387, and SEL-751A, at discounted prices.
Each shipment includes an original SEL product CD, the American SEL microprocessor-based protection device factory test report, and import customs declaration documents.
Please feel confident in our cooperation. The product comes with a one-year warranty and we provide free SEL relay installation and commissioning services. SEL series microprocessor-based protection devices are flagship products of Schweitzer Engineering Laboratories, Inc., a company established in 1982.
Schweitzer specializes in the development, research, production, sales, and after-sales technical service of power system relay protection, covering power generation, transmission, distribution, and industrial sectors. The company holds the internationally recognized ISO9001 quality certification (successfully passed in 1994 and recertified twice).
All design, manufacturing, sales, and after-sales service processes at SEL are subject to rigorous quality testing and standardized management control. SEL protection products are multi-functional microprocessor-based protection devices.
In addition to their superior protection functions, they also possess powerful measurement, control, communication, and programmable logic controller (PLC) functions; a single device can perform almost all secondary functions. SEL protection is the ideal choice for microprocessor-based protection products in substations worldwide.
Original American SEL microprocessor-based protection devices:
- Standard 4-phase voltage and 3-phase current output, allowing for convenient combination outputs for various types of protection tests. Each phase can output 120V, and the current can be 120A in three parallel phases. The fourth phase voltage Ux is a multi-functional voltage item, which can be set to four different output conditions: 3U0, synchronization voltage detection, or any voltage value. It features an original American SEL microprocessor protection device.
- Standalone operation: convenient single-unit operation via a flexible rotary mouse and a large LCD screen with full Chinese display. It can complete most on-site testing and verification work, verify various relays and microprocessor protection devices, and simulate various complex transient, permanent, and transitional faults for complete system testing.
- Ready to use right out of the box, easy and quick to operate.
- Dual operation modes: connect to a computer and run using a full suite of Chinese operating software on the Windows platform. This allows for various large-scale, complex, and highly automated verification tasks. It can It can easily test and scan various protection settings, perform fault playback, store test data in real time, display vector diagrams, and print easily test and scan various protection settings, store test data in real time, display vector diagrams, draw fault waveforms, and print reports online. Reports online.
- Abundant switch contacts: the relay protection tester has 8 input contacts and 4 pairs of dry contact outputs. The input contacts are compatible with dry contacts and 0-250V potential contacts, and can intelligently and automatically identify them. Input and output contacts can be expanded according to user needs.
- Large screen LCD display. the display screen. The operation interface and test results are displayed in Chinese. The display is intuitive and clear.
- Self-protection. It adopts a reasonably designed heat dissipation structure and has reliable and perfect multiple protection measures and power soft start, as well as certain fault self-diagnosis and interlocking functions. The original American SEL microcomputer protection device SEL-351A, SEL-551, SEL-751A and other popular models are available at a lower discount price.
- It has an independent dedicated DC power output. The device has a dedicated adjustable DC power output of 110V and 220V.
- High cost performance. in various types of substations. This provides great convenience for substation design and computer networking.
- The hardware uses chips that improve technical performance. The CPU uses an 80C196KB chip, the measurement is a 14-bit A/D conversion, and there are as many as 24 analog input circuits. The acquired data is processed by a DSP signal processing chip. High-speed Fourier transform is used to obtain the fundamental to the 8th harmonic. Special software automatic correction ensures high measurement accuracy. By using dual-port RAM and CPU to convert data, a multi-CPU system is formed. Communication is carried out using CAN bus. It has the characteristics of high communication speed (up to 100MHz, generally running at 80 or 60MHz) and strong anti-interference ability. On-site observation and setting of various protection modes and protection parameters can be easily carried out through the keyboard and LCD display unit.
- The hardware design adopts special isolation and anti-interference measures in power supply, analog input, switch input and output, communication interface, etc., with strong anti-interference ability. In addition to centralized panel, it can be directly installed on switch cabinet.
- The software has rich functions. In addition to completing various measurement and protection functions, it can complete fault recording (1-second high-speed fault recording and 9-second fault dynamic recording), harmonic analysis and low current grounding line selection functions by cooperating with the host computer.
- RS232 and CAN communication methods can be selected, and multiple remote transmission protocols are supported, which is convenient for networking with various computer management systems.
- A wide temperature range background 240×128 large screen LCD liquid crystal display is adopted, which is convenient to operate and beautiful in display.
- It has high integration, small size and light weight, which is convenient for centralized panel installation and decentralized installation on switch cabinets. Functional application of SEL microcomputer protection device: Feeder protection - It has comprehensive protection functions including inverse time overcurrent, directional overcurrent, automatic reclosing, overvoltage/undervoltage, frequency, second and fifth harmonic blocking, optional low energy consumption analog (LEA) voltage input, IEC cable/line thermal element, islanding effect detection and other comprehensive protection functions, which can protect radial and ring distribution circuits. Sensitive Neutral Point Input - Utilizing a 200mA neutral point current input option with directional control, it protects high-resistance grounded, ungrounded, and arc suppression coil grounded systems. The 200mA neutral point current input option can also be used for non-directional SER protection. Arc Detection - Optional arc detection capability improves personnel safety. The SEL-751 offers a combination of light intensity and high-speed overcurrent detection for arc events, providing a fast and safe solution. High Impedance Fault Detection - Employing Arc Sensing Technology (AST), it can detect open circuits, even on poorly contacted surfaces. The AST algorithm can detect arc flashes caused by some high-impedance faults, which can be used for alarms or circuit breaker tripping. This technology provides an additional layer of protection compared to traditional feeder protection methods. What is the difference between the American SEL-351A microprocessor protection device and the American SEL-351 relay? is based on the SEL-351-5 relay hardware. The main differences between the SEL-351 and SEL-351A relays are: SEL-351A Relay: ● Only available in a 2U, 19" screw terminal block chassis, rack-mount or panel-mount, with 8 output contacts and 6 optically isolated input contacts. ● Basic configuration only includes front panel indicator lights (but a style with an 8-button LCD is available by order). ● Only for connections with terminal modules. ● "Similar wiring" terminal block features compatible with SEL-200 series relays. US SEL-351A Relay SEL 351A, P/N: 0351A032X3E54X1 Actual product image: We are a leading distributor of SEL microprocessor-based protection devices and SEL relays from the USA. Our popular models include: SEL-351A (relay models: 0351A00H, 0351A003, 0351A004), SEL-551 (P/N: 0551003X531X), SEL 351A (P/N: 0351A032X3E54X1), SEL-751A, SEL-0387E004X13XX61, SEL-0787EX1G1G0X71810100, SEL-751A01G1G3G73810100, and SEL-0351A030X4B15X1. American SEL microprocessor protection device SEL-055100CX132X
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| Brand Name: | SEL | Certification: | ISO9001, CE |
|---|---|---|---|
| Place of Origin: | China | Condition: | New |
| Warranty: | 1 year | Customized sourcing: | available |
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SEL-351A Microcomputer Protection Device
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