Primary Current Injection Testers

A Primary Current Injection Tester is designed for testing protective relay and circuit breakers. It also tests the turns ratio of current transformers at high variable currents.

A test current is injected into the primary side of a system to determine how it behaves at particular levels of current. This test makes it possible to determine whether the relay will trip and for how long the current needs to flow before the trip is initiated.

Independent loading scenarios on each phase can be applied.


Area of Usage


  • Three phase primary current injection
  • Testing of protection relays
  • Thermal and magnetic device testing
  • Temperature rise and trip test of circuit breakers and junction points


Operating Instruction


Depending on the test to be performed, turn the position switch to the proper selection (example : 3x2.5 V 4000 A or 3x400 V 45 A). Install the intermediate connections with minimum 2A/mm2 current density cables which have equal cross-sections and equal length. Due to the effect of inductance, if any gap is left between the current carrying cables, maximum current can not be reached. In this case, the best solution is to have a touch between current carrying cables. Thermometer probes must be connected to the measurement points with tongs or tapes.



Technical Features AK23 (3x30kVA) AK43 (3x60kVA) AK63 (3x120kVA)
Input 3x400 V
130 A
3x400 V
260 A
3x400 V
520 A

First Output 3x(0-400) V
0-130 A AC
3x(0-400) V
0-260 A AC
3x(0-400) V
0-520 A AC
Second Output 3x(0-15)V
3x(0-2000)A AC
3x(0-4000)A AC
3x(0-6000)A AC
Weight (kg) 500 640+100 700+100
Dimensions (mm) 700x1000x1600 700x1000x1600 1000x2000x1200
Transport With wheels
Measurement of Temperature (8 probes) K type thermocouple 4 meters 400°C
Ammeters 3x(0-2.00)kA 3x(0-4.00)kA 3x(0-6.00)kA
Cooling Methods FAN WATER 22°C WATER 22°C
Computer Interface (optional) RS232/RS485 (Wireless on demand)
Data Logger (optional) Up to 32 temperature probes