STEM-N series current transformers are designed for indoor installation with low environmental pollution. Indoor current transformers are installed in medium voltage switchgear and are designed to transmit measurement information signals to measuring instruments, protection, automation, signaling and control devices in alternating current networks with a frequency of 50 or 60 Hz.
The current transformers have a cast housing made of epoxy compound by injection molding.


  • Rated voltage up to 42 kV
  • Rated current up to 4000 A
  • Rated thermal current up to 40 kA
  • Number of secondary windings from 1 to 5
  • Winding accuracy class for measurement 0.2; 0.2S; 0.5; 0.5S; 1; 3;
  • Winding accuracy class for protection 5P,10P;
  • Switching ratio of transformation in the ratio 1:2 on primary or secondary conclusions.
  • Ambient conditions: temperature from + 10° to +55°.


  • Lack of any maintenance throughout the entire period of operation
  • Fireproof design
  • Possibility of installation in any plane
  • High loads for all accuracy classes
  • Low partial discharge (PD)
  • Resistance to aggressive environmental conditions
  • The hydrophobic material exhibits excellent outdoor performance and also minimizes the possibility of arcing.
  • No ozone depleting gases

Transformers meet the requirements of IEC, ANSI, IEEE, GOST standards.