The SIL-A is a feeder relay with overcurrent and earth fault protection for primary and secondary distribution with auxiliary power supply 24-230 Vac/dc. The current measurement is obtained by standard current transformers /1 or /5.

• Metallic box with high electromagnetic compatibility level (EMC) and a wide range of operating temperatures.
• Direct signalling/control of the circuit breaker (52 function) and the recloser (79 function).
• Zone selection interlocking – ZSI (68 function) is available through configurable inputs and outputs thanks to the programmable logic (PGC).
• In case a CB is manually closed, a switch on to an existing fault may occur. This fault condition is critical if the overcurrent protection function does not clear the fault until the adjusted time delay is finished. It is necessary, in those cases, to clear the fault quickly using SOTF function.
• To allow the communication, relays are provided with a local micro USB front port and with remote communication with different options (ports and protocols) on the rear side:
  • 1 RS485 Port: IEC60870-5-103, Modbus RTU or DNP3.0 Serial (selectable by general settings).
  • 1RS485 Port: IEC60870-5-103, Modbus RTU or DNP3.0 Serial (selectable by general settings) + 1 RJ45 Port: Modbus TCP/IP or IEC60870-5-104 (selectable by general settings).
  • 1 RS485 Port: IEC60870-5-103, Modbus RTU or DNP3.0 Serial (selectable by general settings) 1 RJ45 Port: IEC61850
• The SIL-A has up to 6 configurable inputs and up to 6 configurable outputs (depending on model).
• SIL-A is fitted with the demand of current (Load Data Profiling) with the following characteristics:
• The number of records: 744.
• Recording mode circular.
• Sampling rate (interval): configurable through communications (1-60 min).
• SIL-A is provided with non-volatile RAM memory in order to store up to 2048 events and configurable number of disturbance fault recording (DFR), maintaining date & time thanks to its internal RTC (real Time Clock):
• 5 records in data and COMTRADE format (260 cycles each record): 1 to 8 pre-fault cycles + 252 to 259 postfault cycles.
• 25 records in data and COMTRADE format (60 cycles each record): 1 to 8 pre-fault cycles + 52 to 59 postfault cycles.
• 50 records in data and COMTRADE format (30 cycles each record): 1 to 8 pre-fault cycles + 22 to 29 postfault cycles.
• 100 records in data and COMTRADE format (15 cycles each record): 1 to 8 pre-fault cycles + 7 to 14 postfault cycles.),
• The oscillography is downloaded by a communications port. The SICom communications program allows the oscillography record to be downloaded and saved in COMTRADE format (IEEE C37.111-1991).