Siemens SIPROTEC 5 7SA87 Distance Protection Relay

Siemens SIPROTEC 5 7SA87 Distance Protection Relay Suppliers,Exporters in India

ARP IMPEX is a supplier and exporter of Siemens SIPROTEC 5 7SA87 Distance Protection Relays in India. We supply against exact Siemens part-number requirements for high-voltage transmission lines, utility substations, grid interconnections, protection-panel upgrades and replacement projects.

The Siemens SIPROTEC 7SA87 is used where the line-protection scheme requires selective one-pole as well as three-pole tripping. This is its main difference from distance relays designed only to disconnect all three phases.

On an overhead transmission line, many faults involve only one phase. With a correctly designed protection scheme, the 7SA87 can trip the affected phase and allow the healthy phases to remain in operation. This helps maintain network stability and continuity while the faulted phase goes through the reclosing sequence.

The relay has a minimum tripping time of 9 ms and is intended mainly for high-voltage line protection. It can be applied to radial networks, parallel lines, ring systems and circuits supplied from one or both ends.

Distance protection works by identifying whether the measured line impedance has entered a configured protection zone. The 7SA87 supports different distance-protection methods and can also provide directional overcurrent backup, earth-fault protection and breaker-related functions where these form part of the ordered configuration.

Its modular construction allows the input, output and communication arrangement to match the protection panel. A smaller installation may need only the base hardware, while a large transmission-line panel may require additional breaker contacts, alarms, interlocks and communication channels.

Fault Locator Plus can help estimate the fault position, including on routes with different line sections. The relay can also support targeted automatic reclosing of an overhead-line section through the AREC function.

For Siemens SIPROTEC 7SA87 price and availability, send the complete Siemens MLFB, required quantity and destination country.

Technical Specifications

• Brand: Siemens
• Product family: SIPROTEC 5
• Model: 7SA87
• Product type: Modular numerical distance protection relay
• Main application: High-voltage line protection
• Protected circuits: Overhead lines, cable circuits and mixed routes
• Tripping arrangement: Selectable one-pole and three-pole tripping
• Minimum tripping time: 9 ms
• Distance measurement: Six independent measuring loops
• Main protection: Phase and earth distance protection
• Backup protection: Directional and non-directional overcurrent protection
• Analogue inputs: Standard arrangements with 4 CT/4 VT or 8 CT/8 VT inputs
• Binary inputs: Up to 31, depending on the selected hardware
• Binary outputs: Up to 46, depending on the selected hardware
• Hardware: Modular and expandable SIPROTEC 5 construction
• Housing width: From one-third to two full 19-inch rack widths
• Display options: Small display, large display or no display
• Engineering software: Siemens DIGSI 5
• Communication: Integrated Ethernet with optional plug-in modules
• Communication expansion: Up to four plug-in communication modules
• Redundancy: PRP and HSR options for applicable Ethernet arrangements
• Control: Circuit-breaker control, synchrocheck and interlocking
• Recording: Event, fault and disturbance recording
• Environmental protection: Conformal-coated electronic boards

Siemens offers several hardware arrangements under the 7SA87 range. The complete input and output configuration, auxiliary supply, display, communication ports and protection functions must be checked from the full article number.

Protection Functions

Depending on the ordered configuration, the Siemens SIPROTEC 7SA87 can provide:

• Phase and earth distance protection
• Classic distance-protection characteristics
• Reactance-method distance protection
• Transformer impedance backup protection
• Directional phase overcurrent protection
• Directional earth-fault protection
• Sensitive earth-fault protection
• Intermittent and transient earth-fault detection
• Power-swing blocking
• Out-of-step protection
• Current-transformer saturation detection
• Teleprotection for distance protection
• Weak-infeed echo and tripping
• One-pole and three-pole automatic reclosing
• Circuit-breaker failure protection
• Fault-location functions
• Synchrocheck and switching supervision
• Undervoltage and overvoltage protection
• Frequency protection and load shedding
• Trip-circuit supervision
• Arc protection on applicable configurations

The full protection package varies between article numbers. A buyer should not assume that every optional function is included only because the front model states 7SA87.

Features

• One-pole and three-pole tripping for high-voltage line protection
• Fast fault clearance with a minimum tripping time of 9 ms
• Suitable for overhead transmission lines and cable circuits
• Works in radial, parallel, ring and double-end-fed networks
• Six independent distance-measuring loops
• Selective operation for phase and earth faults
• Single-pole automatic reclosing for applicable overhead-line schemes
• Fault Locator Plus helps identify the affected line section
• Detects CT saturation while maintaining fast relay operation
• Power-swing blocking reduces unwanted tripping during system disturbances
• Directional overcurrent functions provide backup protection
• Modular hardware allows the I/O arrangement to match the panel
• Up to four communication modules can be selected
• IEC 61850 communication is available for modern substations
• PRP and HSR support redundant station communication
• Conformal coating protects the electronics in demanding environments
• Web browser access provides operating and diagnostic information
• Suitable for new transmission projects and existing relay replacement

Why One-Pole Tripping Matters

A standard three-pole trip opens all phases of the circuit, even when the fault affects only one phase. In a phase-selective scheme, the 7SA87 can trip the faulted phase and start a one-pole reclosing sequence.

This arrangement is mainly used on important overhead transmission lines. It can help the power system remain stable during temporary phase-to-earth faults caused by lightning, contamination or external contact.

One-pole tripping should only be used where the circuit breakers, current and voltage transformers, protection communication and approved utility scheme support phase-selective operation.

Applications

The Siemens SIPROTEC 5 7SA87 Distance Protection Relay is used for:

• High-voltage overhead transmission lines
• Extra-high-voltage transmission systems
• Underground power cable circuits
• Mixed overhead-line and cable routes
• Single-pole line protection schemes
• Three-pole distance protection schemes
• Lines supplied from one end
• Lines supplied from two ends
• Parallel transmission lines
• Open and closed ring networks
• Meshed transmission networks
• Grid interconnection lines
• Utility transmission substations
• Breaker-and-a-half substations
• Power-generation substations
• Renewable-energy evacuation lines
• Wind-farm grid connections
• Solar power transmission links
• Transformer feeder backup protection
• Backup for line differential protection
• Substation extension and modernisation projects
• Replacement of existing Siemens distance relays

The 7SA87 is mainly selected for lines where fast phase-selective operation, single-pole reclosing and flexible communication are important parts of the approved protection scheme.

Siemens 7SA86 and 7SA87 Difference

Both are modular SIPROTEC 5 distance protection relays with fast operation and expandable hardware.

The main difference is the tripping arrangement:

• SIPROTEC 7SA86: Three-pole tripping
• SIPROTEC 7SA87: One-pole and three-pole tripping

The 7SA87 is normally selected for high-voltage overhead transmission lines requiring phase-selective tripping and single-pole automatic reclosing.

The 7SA86 may be more appropriate where the protection scheme always disconnects all three phases. The correct selection should follow the approved protection drawing and utility specification.

Replacement and Ordering Information

A request for “Siemens 7SA87 Relay” is not enough to prepare an accurate quotation. Different article numbers can have different analogue inputs, binary contacts, displays, communication modules and function packages.

Please share:

• Complete Siemens MLFB or article number
• Required quantity
• Destination country
• Required communication interface, where specified
• For replacement requirements, also send:
• Clear photograph of the relay nameplate
• Front-panel photograph
• Rear-terminal photograph
• Existing relay model and firmware details, where available
• Information about the relay installed at the remote line end
• Existing protection communication medium, where applicable

If the article number is unavailable, share the existing relay model and confirm whether one-pole tripping and automatic reclosing are required.

Siemens SIPROTEC 5 7SA87 Supplier and Exporter in India

ARP IMPEX supplies Siemens SIPROTEC 5 7SA87 Distance Protection Relays for transmission utilities, EPC contractors, power plants, switchgear manufacturers, protection-panel builders and industrial power projects.

We handle requirements for Siemens 7SA87 one-pole distance relays, high-voltage line protection, single-pole reclosing relays, IEC 61850 distance protection, substation modernisation and replacement of existing Siemens numerical relays.

The Siemens SIPROTEC 7SA87 price depends on the complete article number, analogue inputs, binary I/O, communication modules, housing arrangement, enabled functions and required quantity.

Send the complete Siemens part number, quantity and destination country for price, availability and export quotation.