Siemens Siprotec 5 7SL87 Line Differential & Distance Protection Relay

The combined line differential and distance protection SIPROTEC 7SL87 Distance Protection Relay is part of the advanced SIPROTEC 5 Protection Relay Series, which offers modular, flexible, and intelligent digital field devices. Moreover, this series is designed to meet modern power system protection requirements. Additionally, with its modular architecture and flexibility, the SIPROTEC 7SL87 easily adapts to different grid configurations.

Furthermore, when combined with the high-performance DIGSI 5 Engineering Tool, the SIPROTEC 7SL87 fits perfectly for protection, control, monitoring, and measuring applications in electrical energy systems. As a result, utilities and industries can enhance grid reliability and operational efficiency.

Main Function

• Differential and distance protection ensure accurate fault detection and system stability.

Tripping

• 1-pole and 3-pole tripping options are supported.

• Moreover, the relay offers a minimum tripping time of 9 ms. Therefore, it enables fast fault clearance and improves system protection.

Inputs and Outputs

• The relay provides 12 predefined standard variants with 4/4 or 8/8 current and voltage transformers.

• It includes 5 to 31 binary inputs.

• It supports 8 to 46 binary outputs, offering flexibility for various applications.

Hardware Flexibility

In addition, the device features a flexibly adjustable I/O quantity structure within the scope of the SIPROTEC 5 modular system. Consequently, engineers can configure the relay according to specific project needs. Finally, the width of the housing ranges from 1/3 × 19” to 2/1 × 19”, providing convenient installation options for different panel configurations.

All functions can be configured freely with DIGSI 5. For the application of some of the functions, you require the appropriate number of free function points within the device. The function point calculator in the online configurator provides support in determining the required number of function points for your device.

Functions

• Fast tripping time of 9 ms for rapid fault isolation and improved system protection.

• Adaptive differential protection ensures high sensitivity and stability during transformer faults and CT saturation.

• Supports 1-pole and 3-pole automatic reclosing for quick system restoration.

• Provides distance protection options such as classic distance, reactance method (RMD), and impedance protection.

• Includes directional backup protection and several additional protective functions.

• Offers power-swing blocking and out-of-step protection to maintain grid stability.

• Detects ground faults in isolated or arc-suppression grounded systems using multiple methods such as 3I0>, V0>, harmonic, and admittance detection.

• Supports pulse location methods for accurate ground-fault identification.

• Detects current-transformer saturation for reliable and precise tripping.

• Includes arc protection for improved equipment and personnel safety.

• Provides automatic load shedding during underfrequency conditions.

• Supports reactive power undervoltage protection (QU protection).

• Measures current and voltage signals up to the 50th harmonic for precise monitoring and protection.

• Includes control, synchrocheck, and switchgear interlocking protection.

• Features a graphical logic editor to create advanced automation functions.

• Displays single-line diagrams on small or large device screens.

• Provides Ethernet RJ45 ports for DIGSI 5 engineering and IEC 61850 communication.

• Supports pluggable communication modules for IEC 61850, IEC 60870-5-103/104, Modbus TCP, DNP3, and PROFINET IO.

• Enables secure communication via optical fiber, two-wire links, and communication networks.

• Ensures reliability with PRP and HSR redundancy protocols.

• Includes advanced cybersecurity features aligned with NERC CIP requirements.

• Functions as a Phasor Measurement Unit (PMU) using the IEEE C37.118 protocol.

• Supports precise time synchronization via IEEE 1588.

• Provides fault recording up to 80 s at 8 kHz or 320 s at 2 kHz.

• Includes testing and commissioning support tools.

• Offers flexible I/O configuration within the SIPROTEC 5 modular system.

Siemens Siprotec 5 7SL87

SIPROTEC 5 is part of the new generation of incomparable modular, flexible, and intelligent digital field devices. With modularly designed hardware and software and its high-performance DIGSI 5 engineering tool, the SIPROTEC 5 product family of field devices is perfect for protection, control, monitoring, and measuring applications in electrical energy systems. SIPROTEC 5 offers a wide product range with modular elements for every application and requirement.