7SJ64 Relay
- 2. Description The SIPROTEC 4 7SJ64 can be used as a protective control and monitoring relay for distribution feeders and transmission lines of any voltage in networks that are earthed (grounded), low-resistance earthed, unearthed, or of a compensated neutral point structure. The relay is suited for networks that are radial or looped, and for lines with single or multi-terminal feeds. The SIPROTEC 4 7SJ64 is equipped with a synchronization function which provides the operationmodes ‘synchronization check’ (classical) and ‘synchronous/asynchronous switching’ (which takes the CBmechanical delay into consideration). Motor protection comprises undercurrent monitoring, starting time supervision, restart inhibit, locked rotor, load jamprotection as well asmotor statistics. The 7SJ64 is featuring the "flexible protection functions".Up to 20 protection functions can be added according to individual requirements. Thus, for example, rate-of-frequency-change protection or reverse power protection can be implemented.
- 3. Description The relay provides easy-to-use local control and automation functions. The number of controllable switchgear depends only on the number of available inputs and outputs. The integrated programmable logic (CFC) allows the user to implement their own functions, e.g. for the automation of switchgear (interlocking). CFC capacity ismuch larger compared to 7SJ63 due to extended CPU power. The user is able to generate user-defined messages as well. The flexible communication interfaces are open formodern communication architectures with control systems.
- 4. Protection functions Overcurrent protection Directional overcurrent protection Sensitive dir./non-dir. earth-fault detection Displacement voltage Intermittent earth-fault protection Directional intermittent ground fault protection High-impedance restricted earth fault Inrush restraint Motor protection Overload protection Temperature monitoring Under-/overvoltage protection Under-/overfrequency protection Rate-of-frequency-change protection Power protection (e.g. reverse, factor) Undervoltage-controlled reactive power protection Breaker failure protection Negative-sequence protection Phase-sequence monitoring Synchronization
- 5. Monitoring functions Operational measured values V, I, f,... Energy metering values Wp,Wq Circuit-breaker wear monitoring Slave pointer Trip circuit supervision Fuse failure monitor 8 oscillographic fault records Motor Statistics Control functions/programmable logic Flexible number of switching devices Position of switching elements is shown on the graphic display Local/remote switching via keyoperated switch Control via keyboard, binary inputs, DIGSI 4 or SCADA system Extended User-defined logic with CFC (e.g. interlocking)
- 6. System interface – IEC 60870-5-103/ IEC 61850 – PROFIBUS-FMS/-DP – DNP 3.0/DNP3 TCP/MODBUS RTU Service interface for DIGSI 4 (modem) Additional interface for temperature detection (RTD-box) Front interface for DIGSI 4 Time synchronization via IRIG B/DCF77 Communication interfaces
- 7. Application The SIPROTEC 4 7SJ64 unit is a numerical protection relay that also performs control and monitoring functions and therefore supports the user in cost-effective power system management, and ensures reliable supply of electric power to the customers. Local operation has been designed according to ergonomic criteria. A large, easy-to-read graphic display was a major design aim
- 8. Construction Connection techniques and housing with many advantages 1/3, 1/2 and 1/1-rack sizes These are the available housing widths of the 7SJ64 relays, referred to a 19” module frame system. This means that previous models can always be replaced. The height is a uniform 244 mm for flush-mounting housings and 266 mm for surfacemounting housings for all housing widths. All cables can be connected with or without ring lugs. Plug-in terminals are available as an option. It is thus possible to employ prefabricated cable harnesses. In the case of surface mounting on a panel, the connection terminals are located above and below in the form of screw- type terminals. The communication interfaces are located in a sloped case at the top and bottom of the housing. The housing can also be supplied optionally with a detached operator panel (refer to Fig. 5/168), or without operator panel, in order to allow optimum operation for all types of applications.
- 9. Protection functions Time-overcurrent protection This function is based on the phase-selective measurement of the three phase currents and the earth current (four transformers). Three definite-time overcurrent protection elements (DMT) exist both for the phases and for the earth. The current threshold and the delay time can be set in a wide range. In addition, inverse-time overcurrent protection characteristics (IDMTL) can be activated. The inverse-time function provides – as an option – voltage-restraint or voltage-controlled operating modes. With the "flexible protection functions", further definite-time overcurrent stages can be implemented in the 7SJ64 unit.
- 10. Functions Motor control The SIPROTEC 4 7SJ64 with high performance relays is well-suited for direct activation of the circuit-breaker, disconnector and earthing switch operating mechanisms in automated substations. Chatter disable Chatter disable feature evaluates whether, in a configured period of time, the number of status changes of indication input exceeds a specified figure. If exceeded, the indication input is blocked for a certain period, so that the event list will not record excessive operations. Indication derivation A further indication (or a command) can be derived from an existing indication. Group indications can also be formed. The volume of information to the system interface can thus be reduced and restricted to the most important signals.
- 11. Communication In terms of communication, the units offer substantial flexibility in the context of connection to industrial and power automation standards. Communication can be extended or added on thanks to modules for retrofitting on which the common protocols run. Therefore, also in the future it will be possible to optimally integrate units into the changing communication infrastructure, for example in Ethernet networks (which will also be used increasingly in the power supply sector in the years to come). Serial front interface There is a serial RS232 interface on the front of all the units. All of the unit’s functions can be set on a PC by means of the DIGSI 4 protection operation program. Rear-mounted interfaces A number of communication modules suitable for various applications can be fitted in the rear of the flush-mounting housing. PROFIBUS-DP protocol PROFIBUS-DP is the most widespread protocol in industrial automation. Via PROFIBUS-DP, SIPROTEC units make their information available to a SIMATIC controller or, in the control direction, receive commands from a central SIMATIC. Measured values can also be transferred
- 14. Mob No: Mr. Piyush Rathi- +91-9819614841 Website: www.reliservsolution.com Email-ID: piyush@reliserv.in sales1@reliserv.in Address: Office No: 9, Space Heights, Plot No. 53/54 , Sector 34, Kamothe,Navi Mumbai- 410209 Contact us