Siemens Siprotec 5 7SK85 Motor & Generator Protection Relays

The SIPROTEC 7SK85 Motor & Generator Protection Relay is part of the modular SIPROTEC 5 protection and control system series. It is specifically designed to protect motors of all sizes. Moreover, with its flexibility and the powerful DIGSI 5 engineering software, the device supports protection, control, monitoring, and measurement functions in modern electrical energy systems.

Main Function:
Primarily, the relay provides reliable motor protection for motors of all sizes. In addition, it supports three-pole tripping for effective fault isolation.

Inputs and Outputs:
Furthermore, the device offers flexible configuration options:

• 3 predefined standard variants with 4 current transformers and 4 voltage transformers

• 11 to 27 binary inputs

• 9 to 17 binary outputs

Hardware Flexibility:
In addition, the modular SIPROTEC 5 concept allows flexible expansion of the I/O structure. Engineers can easily adapt the device to different application requirements. For example, 1/6 expansion modules can be added to increase functionality. The relay is also available with a large display, a small display, or without a display, depending on operational needs.

Housing Options:
Moreover, the device supports multiple housing widths ranging from 1/3 × 19-inch to 2/1 × 19-inch, which simplifies installation in various panel configurations.

Configuration and Engineering:
Finally, users can configure all functions freely using DIGSI 5. However, some functions require a sufficient number of available function points within the device. Therefore, the function point calculator in the online configurator helps engineers determine the exact number of function points required for a specific application.

FURTHER FUNCTIONS

• Motor protection functions: Startup time monitoring, thermal overload protection for stator and rotor, restart inhibit, unbalanced-load protection, load-jam protection
• Stator and bearing temperature monitoring via temperature sensors with external RTD unit
• Differential motor protection as fast short-circuit protection for motors of high power
• Sensitive ground-fault protection (directional, non-directional) to detect stator ground faults
• Directional and non-directional overcurrent protection (short-circuit protection) with additional functions
• Detection of ground faults of any type in isolated or arc-suppression-coil-ground power systems using the following functions: 3I0>, V0>, fleeting contact, Cos-/SinPhi, harmonic, dir. detection of intermittent ground faults and admittance
• Ground fault detection using the pulse location method
• Overvoltage and undervoltage protection
• Arc protection
• Power protection, configurable as active or reactive power protection
• Detection of current and voltage signals up to the 50th harmonic with high accuracy for selected protection functions (such as thermal overload protection) and operational measured values
• Control, synchrocheck and switchgear interlocking protection
• Graphical logic editor to create powerful automation functions in the device
• Integrated electrical Ethernet RJ45 for DIGSI 5 and IEC 61850 (reporting and GOOSE)
• Up to 4 pluggable communication modules, usable for different and redundant protocols (IEC 61850, IEC 60870-5-103, IEC 60870-5-104, DNP3 serial and TCP, Modbus TCP, PROFINET IO)
• Cyber security to NERC CIP and BDWE Whitepaper requirements
• Secure serial protection data communication, even over great distances and all available physical media (optical fiber cable, 2-wire connections and communication Networks)
• Capturing operational measured variables and protection function measured values to evaluate the plant state, to support commissioning, and to analyze faults
• Phasor Measurement Unit (PMU) for synchrophasor-measured values and IEEE C37.118 protocol
• Powerful fault recording (buffer for a max. record time of 80 sec. at 8 kHz or 320 sec. at 2 kHz)
• Flexibly adjustable I/O quantity structure within the scope of the SIPROTEC 5 modular system

SIPROTEC 7SK85 Motor & Generator Protection Relay

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 are 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.