LV Systems

Current Transformer

A Current Transformer or CT is very essential equipment installed in an electrical substation for electrical measurement and protection purpose. If a current transformer does not perform properly, there may be huge disturbance in the system due to malfunctioning of protection relays. So far accurate measurement and smooth operation of electrical power system, CTs must be properly maintained. A schedule of such maintenance of Current Transformer is preferred below for ready reference.


  • Primary injection Test
  • Insulation resistance Test
  • Checking Tightness of control wiring at Terminals
  • Thermography Test at CT terminals
  • General checking of CTs for any abnormal condition