High Voltage Test  Laboratory

In the CERB Group we perform continuous control over the quality of the repair works, in accordance with the valid Bulgarian and international standards. Aiming to offer a complex service to its clients, in 2017 the company invested in the creation of a modern High Voltage Test Laboratory. The laboratory is certified as per BDS EN ISO/IEC 17025.
Diagnostics & Testing of Transformers
  • Measuring the ohmic resistance ;
  • Measuring the insulation resistance ;
  • Measuring the angle of dielectric losses in frequency range from 15 to 400 Hz ;
  • Measuring the capacity of the object in a frequency range of 15 to 400 Hz ;
  • Measuring the no load losses with decreased or nominal voltage ;
  • Evaluation of the short circuit losses ;
  • Determination of the coefficient of transformation ;
  • Determination of a connection group ;
  • Measuring the winding impedance in a frequency range from 15 to 400 Hz ;
  • Infrared photographing the object ;
  • Testing the magnetic core ;
  • Testing with increased voltage ;
  • Testing with induced increased voltage with frequency 100 Hz ;
  • Testing with impulse voltage – full and cut wave ;
  • Testing with commutation voltage ;
  • Amplitude – frequency characteristic – SFRA ;
  • Measuring the moisture in the solid insulation – as per the FDS-PDC methods of dielectric spectroscopy and recovering voltage RVM ;
  • Measuring partial discharge ;
  • Diagnostics of on load tap changers.
Diagnostics and testing of Rotating Electrical Machines
  • Measuring the ohmic resistance ;
  • Measuring the insulation resistance ;
  • Measuring the angle of dielectric losses in a frequency range of 15 to 400 Hz ;
  • Measuring the capacity of the object in a frequency range of 15 to 400 Hz ;
  • Spinning the motor with no load ;
  • Infrared photographing the object ;
  • Magnetic testing of the stator ;
  • Testing magnetic cores with up to 4% of the nominal induction and inspection for local faults – EL CID Test ;
  • Testing with increased constant or deviating overvoltage ;
  • Measuring partial discharge ;
  • Dielectric spectroscopy FDS-PDC.
The laboratory disposes of modern measuring equipment, such as :
  • Impulse generator HIGHVOLT impulse waive 1800 kV, 220 kJ ;
  • Resonance system for hi-pot testing ;
  • Motor Generator group ;
  • System for diagnostics of electric equipment Omicron СРС 100 + TD1 ;
  • System for measuring the partial discharges Omicron МPD 600 ;
  • Omicron DIRANA – FDS and PDC+ (frequency spectroscopy and testing
    of other energetics installations) ;
  • Polarization/depolarization current ;
  • System for electromagnetic diagnostics of stators – EL CID TEST.

CERB VVL