Optical instrument current transducers KRISMARS-CT


Download Proposal for investors

Power Industry policies of the Russian Federation have given a top priority for the development of Smart Grid concept. In particular, research and design of non-conventional instrument current and voltage transformers for networks 35 to 110 kV is the task of major importance.

Primary current and voltage sensors of optical type are acknowledged as having the best market potential.


Components: Optical current sensor and optoelectronic unit with a standard signal output or Merging Unit on its end (for Digital Substation applications).

Project status: investment offer.

Operating principle
Magneto-optical (Faraday) effect 

Features and benefits
No magnetizing and magnetic saturation effects within 1 to 1000% current range

For DSS applications
IEC 61850-9-2LE output 

Posible testing tools 
Reference equipment from Mars-Energo

Unique Selling Point

1. Unlike widely spread fiber optic current sensors, an optical current sensor made of standard diamagnetic glass has a number of advantages:

  • While passing throught the glass, a light beam behaves according to the laws of classic optics (no multireflections; no influence of material strains etc.), therefore the required measurement accuracy can be achieved using an optoelectronic unit of considerably simpler design
  • Substantial temperature independence owing to diamagnetic glass selected for the independence of its Verdet constant from temperature changes
  • Better time stability

2. Advantage of Mars-Energo prototype – the transducer can also be used for voltage measurements – the only thing to do is to replace the current (Faraday) optical cell with the voltage (electro-gyration) one


Parameter Value
Operating voltage range 0.4 ... 35 kV
Frequency range 1 ... 10 000 Hz
Primary current range 50 ... 5000 A
Accuracy class
Thermal and electrodynamic withstand
0.2S; 0.5S
100; 150 kA
Output signal:
  • Analogue
  • Digital

1 A; 4 V
according to 61850-9-2LE
 Fiber guide length between the optical sensor and optoelectronic unit  Up to 200 m
 Dimensions and weight
  • Optical sensor
  • Optoelectronic unit

162 х 162 mm, 1 kg, or less
134 х 215 х 450 mm, 3 kg, or less
 Power supply (Optoelectronic unit) 220 V; 50 Hz