6AV6381-2BE07-5AV0

SIPROTEC 7SD80 - Line differential protection

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The line differential protection SIPROTEC 7SD80 has been conceived for selective line protection of power cables and overhead lines up to 24km for all kind of starpoint configurations. The implemented phase comparison algorithm is a fast and stable b for line protection in industry and distribution grids. The protection interface communication is carried out directly without external equipment over copper wires, optical fibers or both in redundancy. The wide scope of non directional and directional functions can be applied miscellaneously as emergency functions as well as backup functions. For instance, the SIPROTEC 7SD80 enables simplified and cost saving concepts for meshed grids and busbar protection by means of reverse interlocking.

Features

Fast and selective tripping is guaranteed even if the communication fails between the relays. The scope of functions includes protection functions as well as functions for control and monitoring. The interoperable connectivity to substation control systems is give by standard protocols like IEC 61850.

The general concept of redundance for protection and its communication gets completed by Ethernet redundancy protocols (PRP, HSR, RSTP) and thus increases the total system availability. Integrated functions for commissioning help and easy settings lead to short commissioning times.

Hardware

• 4 current transbers
• 0/3 voltage transbers
• 3/5/7 binary bs (thresholds configurable using software)
• 5/8 binary outputs (2 changeover)
• 1 life contact
• Pluggable current and voltage terminals.

Product homepage - downloads from the internet (catalogs, certificates, firmware, manuals,...)

www.siemens.com/7SD80

• Integrated interfaces for exchanging differential protec¬tion data (fiber-optic up to 24 km / 15 miles and/or two-wire cop-per cables up to 20 km / 12 miles)
• Transmission of a circuit-breaker intertripping signal and 16 further binary signals to the opposite end.
• Secondary current transber values (1 A / 5 A) settable using DIGSI
• 9 programmable function keys
• 6-line display
• Buffer battery exchangeable from the front
• USB front port
• 2 additional communication ports
• Integrated switch for low-cost and redundant optical Ethernet rings
• Ethernet redundancy protocol RSTP for highest availability
• Relay-to-relay communication through Ethernet with IEC 61850 GOOSE

The SIPROTEC 7SD80 is a numerical line differential protection relay, which in addition to its main function, the selective protection of overhead lines and cables, also covers control and monitoring tasks.

Line protection

SIPROTEC 7SD80 devices are suitable as selective line protection for application in high-voltage and medium-voltage systems of all types of neutral designs (solid, low-resistance or high-resistance earthed, isolated or compensated). Apart from the main protection function, the line differential protection, SIPROTEC 7SD80 offers a lot of additional protection functions. These can be used in parallel as a backup protection function, or as an emergency function if the main protection function fails, and they complement the range of functions of 7SD80 for application in transmission lines.

Control

The integrated control function permits control of disconnect devices, grounding switches or circuit-breakers through the integrated operator panel, binary bs, DIGSI 4 or the control or automation system (e.g. SICAM).

Programmable logic

The integrated logic characteristics (CFC) allow the user to add own functions for automation of switchgear (e.g. interlocking) or switching sequence. The user can also generate user-defi ned messages. This functionality can b the base to create extremely flexible transfer schemes.

Operational measured values

Extensive measured values (e.g. I, V), metered values (e.g. Wp, Wq) and limit values (e.g. for voltage, frequency) provide improved system management as well as simplification by the commissioning As for the operational measured values, a special focus was placed on the measured values critical for differential protection. So, the attenuation values and the signal-to-noise ratio of the communication connection, for example, are acquired and indicated in addition to the measurement of the quality of the telegram exchange per time unit. Particular attention was paid to making the commissioning of the differential protection easier and safer. In this context, the amplitude and angle of the currents and of the voltages, if applicable, are displayed additionally with reference to the local measuring variable. In this way, a possible incorrect connection (polarity reversal) of the current transbers can be detected and eliminated early enough.

Operational indication

Monitoring of operation is ensured and documented by storage of event logs, trip logs, fault records and statistics.

Protection functions

• Differential protection, line 87L
• 3I0 differential protection 87N L
• Ground-fault differential protection for systems with resonant or isolated neutral 87Ns L Optional
• Definite time-overcurrent protection with delay for phase 50 TD (3 stages)
• Definite time-overcurrent protection with delay for earth 50N TD (3 stages)
• Inverse time-overcurrent protection (phase) 51
• Inverse time-overcurrent protection (ground) 51N
• Inrush current detection
• Circuit-breaker failure protection 50BF
• Trip-circuit supervision 74TC
• Lockout 86
• Circuit-breaker intertripping scheme 85 DT
• External trip initiation
• Undervoltage/overvoltage protection 27/59 Optional
• Underfrequency/overfrequency protection 81 U/O Optional
• Directional time-overcurrent protection (phase) 67 (3 stages) Optional
• Directional time-overcurrent protection (ground) 67N (3 stages) Optional
• Automatic reclosing 79 Optional
• Flexible protection functions for current, voltage, power, cosϕ, frequency Partly optional
• Thermal overload protection 49

Control functions /programmable logic

• Commands (e.g. for the control of circuit-breakers, disconnect switches, grounding switches, etc.) through:
  • keyboard
  • binary bs
  • DIGSI 4
  • communication interface
• User-defi ned PLC logic with CFC (e.g. interlocking).

Monitoring functions

• Operational measured values V, I, f
• Energy metering values Wp, Wq
• Circuit-breaker wear monitoring
• Minimum and maximum values
• Trip circuit supervision
• Fast measuring voltage failure “fuse-failure-monitor”
• 8 oscillographic fault records.

Communication interface

• System interface
  • IEC 61850 Edition 1 and 2
  • IEC 60870-5-103
  • MODBUS RTU
  • DNP 3.0
  • PROFIBUS-DP
  • Ethernet redundancy protocols RSTP, PRP and HSR
• Service interface
  • USB front interface for DIGSI 4
  • RS232/RS485 (instead of the system interface)
• Protection interface
  • Fiber-optic connection and/or
  • Two-wire connection.

Hardware

• 4 current transbers
• 0/3 voltage transbers
• 3/5/7 binary bs (thresholds confi gurable using software)
• 5/8 binary outputs (2 changeover)
• 1 life contact
• Pluggable current and voltage terminals.