Siemens SIPROTEC 4 Compact Numerical Protection Relays
Siemens SIPROTEC 4 Compact Numerical Protection Relays Suppliers,Exporters in India
ARP IMPEX is a supplier and exporter of Siemens SIPROTEC 4 Compact Numerical Protection Relays in India. We handle requirements for feeder protection, motor protection, voltage and frequency monitoring, line differential protection, existing panel replacement and industrial substation maintenance.
SIPROTEC 4 Compact is a group of space-saving protection relays developed mainly for medium-voltage distribution systems and industrial electrical networks. The range includes separate models for feeders, motors, voltage and frequency protection, and short line or cable differential protection.
These relays are smaller than many standard SIPROTEC 4 devices, but they are not basic standalone trip units. Depending on the selected model, one device can handle protection, measurements, breaker control, event recording, programmable logic and communication with a plant or substation control system.
The range was widely installed in compact switchgear panels, motor control systems, renewable-energy substations and industrial distribution boards where panel space was limited. Its pluggable current and voltage terminals also made installation and replacement work easier.
A request for “SIPROTEC 4 Compact” alone is not enough to identify the relay. The exact model and full Siemens article number are required because a 7SJ80 feeder relay, 7SK80 motor relay and 7RW80 voltage relay perform different jobs.
For Siemens SIPROTEC 4 Compact relay price and availability, send the complete Siemens part number, required quantity and destination country.
Models Covered Under SIPROTEC 4 Compact
Siemens 7SJ80 Overcurrent and Feeder Protection Relay
The SIPROTEC Compact 7SJ80 is mainly used for feeder, line, overcurrent and earth-fault protection. It can work in networks with solid, resistance-earthed, isolated or compensated neutral arrangements.
Common applications include incoming feeders, outgoing feeders, transformer backup protection, overhead distribution lines, cable feeders and industrial switchgear. Directional functions, voltage protection, automatic reclosing and fault-location functions depend on the ordered version.
Siemens lists several 7SJ80 article numbers under product phase-out, with SIPROTEC 7SX800 shown as the successor for applicable configurations. Exact replacement suitability must still be checked in the full MLFB.
Siemens 7SJ81 Relay for Low-Power Instrument Transformers
The 7SJ81 covers feeder and overcurrent protection applications using low-power current transformers. Selected versions also accept low-power voltage-transformer inputs.
It was developed for compact switchgear systems where smaller sensor arrangements, reduced CT variants, and a wide primary-current measuring range were important. The sensor type and input arrangement must match the installed switchgear and cannot be assumed from the model name alone.
Siemens 7SK80 Motor Protection Relay
The Siemens SIPROTEC Compact 7SK80 is used for the protection of asynchronous motors. It can monitor motor starting, thermal loading, current unbalance, locked-rotor conditions, undercurrent, earth faults and other abnormal operating conditions.
The relay includes five inputs for direct RTD temperature sensors. Additional temperatures can be monitored through a connected thermobox. ATEX-certified 7SK80 versions were also available for applicable motor protection schemes.
Buyers commonly request the 7SK80 for pumps, compressors, fans, conveyors, crushers and other motors where an ordinary overload relay does not provide enough protection or operating information.
Siemens 7SK81 Motor Protection Relay
The 7SK81 performs motor protection duties similar to the 7SK80 but works with low-power current transformers. Optional low-power voltage inputs were also offered.
It was used in compact motor switchgear where sensor-based current measurement formed part of the panel design. Siemens lists the 7SK81 under product phase-out, with 7SY82 identified as a successor for applicable requirements.
Siemens 7RW80 Voltage and Frequency Protection Relay
The Siemens 7RW80 monitors voltage and frequency conditions in distribution systems, transformers and electrical machines.
It can be used for:
- Undervoltage and overvoltage protection
- Underfrequency and overfrequency protection
- Transformer or generator overexcitation protection
- Network decoupling
- Load shedding
- Automatic load restoration
- Vector-jump monitoring
- Synchrocheck on applicable versions
The relay was frequently applied in captive power systems, industrial grids and decentralised generation projects where the installation had to disconnect from an unstable network or shed loads during a frequency drop.
Siemens currently lists 7RW80 article numbers under product phase-out and identifies the 7SX800 as the successor for applicable configurations.
Siemens 7SD80 Line Differential Protection Relay
The SIPROTEC Compact 7SD80 provides differential protection for short overhead lines and underground cable circuits.
It exchanges protection data between both line ends through integrated fibre-optic or two-wire interfaces. Siemens specified distances of up to 20 km over the integrated two-wire connection and up to 24 km over the fibre-optic interface.
The 7SD80 is useful where an existing cable or short line already has copper or fibre communication available. Directional or non-directional overcurrent protection can provide emergency backup if the differential communication channel is unavailable.
Replacement enquiries must include details of the relay installed at both ends of the line.
Communication medium, interface type, firmware and relay configuration must remain compatible.
General Technical Specifications
As SIPROTEC 4 Compact covers several relay types, the technical arrangement changes from one model to another.
General family characteristics include:
- Brand: Siemens
- Product family: SIPROTEC 4 Compact
- Product type: Numerical protection, control and monitoring relays
- Main models: 7SJ80, 7SJ81, 7SK80, 7SK81, 7RW80 and 7SD80
- Primary applications: Feeders, motors, voltage and frequency protection, lines and cables
- Display: Six-line front display
- LED indication: Eight freely assignable LEDs
- Function keys: Nine freely configurable keys
- Front connection: USB interface
- Current terminals: Pluggable terminal blocks
- Voltage terminals: Pluggable terminal blocks
- Rated CT secondary: 1 A or 5 A on applicable conventional CT models
- Engineering software: Siemens DIGSI 4
- Logic: Programmable CFC logic
- Setting groups: Up to four on the main protection models
- Records: Fault, event and disturbance recording
- Control: Circuit-breaker control on applicable versions
- Communication: The protocol and interface depend on the article number
- Mounting: Compact protection and switchgear panels
- Auxiliary supply: Depends on the ordered version
Siemens offered communication options including IEC 61850, IEC 60870-5-103, PROFIBUS DP, DNP3, Modbus RTU and PROFINET across applicable configurations. Not every relay includes every protocol.
Features
Compact Panel Arrangement
The narrow housing makes these relays useful in switchgear panels where there is limited space for protection and control equipment.
Pluggable Measuring Terminals
Current and voltage terminal blocks can be removed during installation or replacement. This helps with panel wiring and avoids unnecessary disturbance to fixed cable connections.
Protection and Breaker Control
Applicable models combine protection with circuit-breaker control, indications and interlocking. This can reduce the number of separate control devices required inside the panel.
Clear Front Operation
The six-line display, LEDs and configurable function keys give operators access to measurements, alarms and switching information from the front of the relay.
DIGSI 4 Configuration
DIGSI 4 is used for protection settings, input and output assignment, logic configuration and record evaluation. Existing DIGSI files can be useful when checking a replacement requirement, but they do not replace the need for the full article number.
Choice of Protection Applications
The family covers different jobs rather than forcing one relay to handle every application:
- 7SJ80 and 7SJ81 for feeder and overcurrent protection
- 7SK80 and 7SK81 for motor protection
- 7RW80 for voltage and frequency protection
- 7SD80 for short line and cable differential protection
Substation Communication
Applicable models can exchange indications, measurements and commands with SCADA or substation automation systems. IEC 61850 GOOSE communication is available on selected configurations.
Suitable for Existing Installations
Many enquiries today are for the replacement of an installed relay rather than selection for a completely new panel. Keeping the same model may reduce panel changes, but only when the hardware, terminals, communication and function package match.
Applications
Siemens SIPROTEC 4 Compact Protection Relays are found in:
- Medium-voltage incoming feeder panels
- Outgoing distribution feeders
- Underground cable feeders
- Overhead distribution lines
- Transformer backup protection
- Industrial motor protection panels
- Pump and compressor control systems
- Fans, blowers and conveyor motors
- Captive power plants
- Utility distribution substations
- Industrial substations
- Renewable-energy substations
- Wind-farm feeder protection
- Solar power evacuation panels
- Network-decoupling schemes
- Underfrequency load-shedding panels
- Generator and transformer voltage supervision
- Short cable differential protection
- Ring distribution networks
- Existing SIPROTEC relay replacement
- Switchgear retrofit and modernisation projects
- Spare-relay requirements for plant maintenance
SIPROTEC 4 Compact Product Status and Replacement
Several SIPROTEC 4 Compact models and article numbers are now in the Siemens phase-out stage. Their successors come from newer SIPROTEC 5 platforms, but there is no single new relay that automatically replaces every Compact device.
For example:
- An applicable 7SJ80 or 7RW80 requirement may move to the SIPROTEC 7SX800.
- A 7SK81 sensor-based motor protection requirement may move to the SIPROTEC 7SY82.
- More complex feeder or motor applications may require another model from the SIPROTEC 5 range.
A new-generation relay may have different dimensions, terminals, software, communication ports and function allocation. It should not be treated as a direct drop-in replacement without checking the complete panel and protection scheme.
Information Required for Quotation
For an accurate quotation, share:
- Complete Siemens MLFB or article number
- Relay model
- Required quantity
- Destination country
For a replacement requirement, also share:
- Clear photograph of the front nameplate
- Photograph of the rear terminals
- Existing communication interface
- DIGSI 4 setting file, where available
- Details of the relay at the opposite line end for 7SD80 requirements
The control voltage, CT arrangement, voltage inputs, binary contacts, communication protocol and function package can differ between two relays carrying the same basic model number.
Siemens SIPROTEC 4 Compact Supplier and Exporter in India
ARP IMPEX supplies Siemens SIPROTEC 4 Compact Protection Relays for utilities, panel builders, EPC contractors, industrial users, power plants and maintenance companies.
We handle enquiries for Siemens 7SJ80 feeder protection relays, 7SK80 motor protection relays, 7RW80 voltage and frequency relays, 7SD80 line differential relays and suitable SIPROTEC 5 replacement models.
Send the complete Siemens part number, required quantity and destination country for price, availability and export quotation.
