SIL-D OC&EF Directional Protection Relays

SIL-D relay is designed to protect MV systems with isolated neutral. In switchgears with isolated neutral, the earth fault calculation cannot be done as an exact value due to it is not dependent from the short circuit power. It depends on the MV system capacitor it is connecting to. For this reason, the earth fault is related with the network voltage and with the features of the lines connected to the mentioned system.

Apart from the phase and neutral instantaneous overcurrent, and protection against phase inverse time overcurrent, the relay provides directional neutral overcurrent and directional isolated neutral overcurrent as well as circuit breaker failure supervision, neutral overvoltage and trip block for switch disconnector.

A recloser is fitted. This automated control shall permit closure (up to five attempts) with the possibility of programming each reclosing time

Further functions have been included, such as the cold load pickup, or the trip circuit supervision.

Main Applications: Distribution and transformation substations. RMUs and SF6 insulated Switchgears.

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SIL-D relay is an overcurrent and directional earth fault protection relay for Primary and Secondary Distribution.

  • Auxiliary power supply (24-220 Vdc / 48-230 Vac).
  • Protection functions: (2) 50 + 50/51 + (2) 50N/G + (2) 50N/51N/67N(1) + 52 + 50BF + 79 + 74TCS + CLP + 86 + 49T + 59N. Optionally, directional isolated neutral overcurrent(2) : 67NI_1 and 67NI_2.
    It includes switch disconnector protection function by means of trip blocking.
  • Function 67NI. Directional neutral isolated overcurrent with two neutral directional units: 67NI_1 and 67NI_2.
    This function is based on two supervisions: The analogue to the one that uses the 67N to check that the residual current is inside the defined area by the settings of directionality, operation angle and halfcone, and the second supervision of the modules of the residual voltage and current.
  • To perform the directional detection, the residual voltage is used as polarization magnitude and the residual current as an operating magnitude. The intervention sector in forward direction is defined in the following way: the operating angle is rotated anticlockwise from the negative residual voltage,-V0 which gives us the maximum torque direction. A cone is drawn, with the half-cone angle adjusted, over this maximum torque direction. In the same way, the intervention sector in reverse direction is defined in the following way: the operating angle is rotated anticlockwise from the positive residual voltage, V0 which gives us the maximum torque direction. A cone is drawn, with the half-cone angle adjusted, over this maximum torque direction.
    When 67NI is not activated the functions works like 50/51G.
  • 5 attempts of reclosing with 79 protection function (Recloser). Direct signalling/control of function 52 (Circuit breaker) and function 79 (Recloser).
  • Metallic box with high electromagnetic compatibility level (EMC) and wide range of operating temperature.
  • 1 rear port on the back with the following options respect to communication protocols:
    • One rear port RS485 with IEC60870-103 or Modbus RTU selectable by settings.
    • One rear port RJ45 with IEC 61850, DNP 3.0 TCP/IP or IEC 60870-5-104 (depending on the model).
  • 5 Oscillographic records, non-volatile RAM memory in order to store up to 200 events and 20 fault reports, without power supply thanks to its internal RTC (Real Time Clock).

50 Phase instantaneous phase overcurrent
50N/G Neutral instantaneous overcurrent calculated/measured
50/51 Inverse time phase overcurrent
50N/51N Inverse time directional
67N neutral overcurrent calculated/measured
50BF Circuit Breaker opening fault
46 Negative sequence instantaneous overcurrent
52 Circuit Breaker monitoring
79 Autorecloser
74TCS Trip circuit supervision
CLP Cold Load Pick-up
86 Trip output lockout with PLC
49T Trip output
67N Inverse time directional isolated neutral overcurrent
59N Instantaneous neutral overvoltage
68 Trip Bus
TB Trip Block for switch disconnector

Communication Software for SIA & SIL protection relays

The SICom PC software has been designed and programmed to gain access to all of Fanox relays information, to modify the settings and configuration, check states and measurements and to analyse and save events and fault reports using a graphic-friendly user interface.

SICom software works with the Windows® Windows 7, Windows 8, Windows 8.1 and Windows 10 operating system.

  • General data reading: Complete model, Version, Serial number, etc.
  • States reading
  • Measurements reading
  • Reading and changing settings
  • Reading and changing configuration
  • Reading and deleting events
  • Reading and deleting fault reports
  • Reading and deleting demand current (load data profiling)
  • Reading and saving oscillographic records in Comtrade format
  • Changing the user passwords
  • Saving and Loading settings files
  • Saving and Loading configuration files
  • Saving events and fault reports
  • Saving demand current (load data profiling)
  • Date-time synchronization
  • Configuring the communication parameters
  • Reading and changing counters
  • Commands for opening and closing the circuit breaker and block/unblock the recloser
  • Configuration of the inputs
  • Configuration of the outputs
  • Configuration of the causes that start a Fault Report

The update of the software does not require any user´s action, this is, if the computer is connected to Internet, SICom updates itself when it is started.
It will allow you to prepare all the settings and relay configurations without having the relay connected to the PC (offline mode), reducing engineering and commissioning time.
SICom program uses Modbus protocol, so only the ports with this protocol can be used to establish the communication.

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