Testing and Measuring Instruments

LET-2000-RD primary test equipment

It allows to perform with sufficient power, all the primary current injections to test the proper function and wiring of all the elements that compose the protection and measuring section in a substation.

The regulation system is based on a continuously variable autotransformer (Variac) that supplies to a power transformer that delivers the high current outputs and isolate the main supply from the load. A built-in ammeter and a timer gives the information about the current value and the operation time of the relay or breaker under test.


  • Permanent current up to 2000A, 4KVA in 4 Ranges.
  • Made up of two units.
  • Built in digital ammeter 0.5% accuracy.
  • Built in digital timer resolution 1 ms.
  • Thermal and shortcircuit protection.


  • Direct and motor overload relay test.
  • In general, primary tests including the complete loop, i.e., current transformer, leads, protective relay and circuit breaker.