SIL-G Generator Protection Relays

SIL-G Generator Protection Relays

The SIL-G is a relay for the protection of generators which is able to protect a generator by means of current, voltage and frequency functions. It is normally used with a circuit breaker as cutting element.

It is the best solution for Cogeneration, it is normaly used in power stations from gas, steam, hydraulic turbine, or diesel driven generators.


  • Protection functions available in SIL-G are the following:
    • 81R, 78, 81 U/O, 27P, 32/40, 59P, 59N, 25, 79, 50P, 50N/G, 67P, 67N, 46, 79, 50BF, 52, 49, 86,CLP, 49T, 74TCS, 37 and IRIG-B.
  • SIL-G monitors differences in voltage magnitudes, phase angles, and frequencies to perform synchronism checks across the circuit breaker. This function can be coordinated with the auto-reclose function (up to five recloses).
  • SIL-G is used with auxiliary power supply (110-230 Vac/ 90-300 Vdc and optionally 24-48 Vdc).
  • Two rear ports on the back for remote communication. Two communication protocols can be used simultaneously:
    • IEC 60870-5-103, IEC 61850, DNP 3.0 or IEC 60870-5-104
  • SIL-G has metallic box with high electromagnetic compatibility level (EMC) and wide range of operating temperature.
  • Direct signalling/control both of the circuit breaker (52 function), both of the recloser (79 function).
  • Its reduced size makes the SIL-G relay easy to install and its light weight helps the customer to save costs in transport.
  • 8 configurable inputs and 7 configurable outputs.
  • 2 Oscillographic records,  20 fault reports and non-volatile RAM memory: stores 1.000 events with date/time even without power supply thanks to its internal RTC.