Instrument Transformers

KSI range of Instrument transformers are electrical devices used to isolate or simply transform voltage or current levels to measurable levels. Typical applications of instrument transformers include Metering - high voltage or high current circuits and Safety - isolating secondary control circuitry from the high voltages or currents.

Typically, the primary of the transformer is connected to the high voltage or high current circuit, and the secondary to a meter or relay.

With the use of Instrument Transformers, the large voltage and current of an AC Power system can be measured by using small rating measuring instrument i.e. 5 A, 110 – 120 V. Also measuring instruments can be standardized. Which results in reduction of cost of measuring instruments.

KSI provides solutions for two types of Instrument Transformers - Current Transformers (CTs) and Potential (Voltage) Transformers (PTs)


  • Designed as per Industry preferred standards of IS, IEC, C-57
  • Standard LTCTs with secondary currents of 5A or 1A
  • Standard LTPTs with secondary voltage range 30V to 0.72kV
  • Custom secondary currents and voltage possible
  • Secondary burden 1VA to 30VA
  • LTCTs with dual rations can be offered
  • Single or three phase units available
  • Varnished Fibreglass/ PVC Tape insulated, Resin cast Or Nylon molded constructions available.
  • Special CT and PT as per customer specific requirement can be done with ease

Reactors and Chokes

KSI range of Line and load Reactors are best in class devices popularly used for reducing Harmonics caused by Variable Frequency Drives (VFDs). Ruggedly constructed, Carefully designed and tested, they are great in absorbing power line disturbances that can damage VFDs and other sensitive instruments on your system. The reactors work on both ends – Line Side and the Load Side to provide an easy solution that minimizes unwanted tripping and harmonic distortions.

Apart from these Line/ Load reactors, KSI provides a wide range of DC Line chokes which provides one of the most convenient methods to filter and control DC bus voltage and current in the system.

For best performance it is suggested to combine the use of both an AC input reactor and DC Line Choke.


    Line/ Load Reactors DC Choke
System Voltage : 110 to 700 V AC 110 to 700 V DC
Type : Single/Three Phase DC
Current Range : 1 to 300 Amps 1 to 300 Amps
Impedance : 1/1.5/2/3/4/5 % 1/1.5/2/3/4/5 %
Frequency : 50/60Hz  
Insulation Class : F & H F & H
Ambient Temp : -5 to +50°C -5 to +50°C
Testing : 1. Full Current Injection
2. Voltage Drop Test
3. Winding Resistance Test
4. H.V. Test
5. Megger Test
1. Full Current Injection
2. Voltage Drop Test
3. Winding Resistance Test
4. H.V. Test
5. Megger Test