22 February 2019
KEMA international laboratory (Netherlands) has finished the tests of two combined non-conventional instrument transformers with digital outputs (CNCIT) produced by Profotech. The CNCIT is branded as Profotech for Russian and CIS market and as CONDIS for distribution by our partner company CONDIS (Switzerland).
The tests were carried out in three modes:
· in configuration of the combined non-conventional instrument transformer (CNCIT) given the connection between current and voltage measurement units and general framing;
· in the operating mode of separate CT (electronic fiber-optic current transformer with digital output EFOCT);
· in the operating mode of separate VT (electronic capacitive voltage divider with digital output ECVD).
Technical specifications of the tested devices:
· Rated voltage from 100 to 145 kV, accuracy class during voltage measurement 0.2 and 3P, rated current 250 A with extended primary current value up to 750% of the rated, accuracy class 0.2S and 5TPE with degree of 63, implemented in one measurement loop.
· Rated voltage from 100 to 145 kV, accuracy class during voltage measurement 0.2 and 3P, rated current 2500 A, accuracy class 0.2S and 5TPE with degree of 63, implemented in one measurement loop.
The tests have been carried out by sample test program which confirms the most important performance indexes:
1. Confirmation of faults during current and voltage measurement by IEC 61850-9-2LE digital output with the number of samples of 80 and 256 for utility frequency period with time synchronization by PTP and 1PPS protocol. Voltage measurement fault was checked in range from 2% rated voltage 100 kV to 190% rated voltage 145 kV. Current measurement fault was checked with accuracy classes 0.2S and 5TPE for rated currents 250 and 2500 A (1–120% from rated current), for 250 A version additional fault control for the compliance with accuracy class 0.2S was carried out in the point of 750% from rated current.
2. Conducted emissions in the mains.
3. Harmonic and interharmonic interference in power supply circuit.
4. Standard and chopped lightning impulse on primary network terminals.
5. Dry and spray test voltage.
6. Partial discharges in high voltage insulation.
7. Level of radiated radio interferences.
8. Heating due to high voltage.
DNV GL is a credible organization with more than 90 years of experience in inspections, testing and certification of electrical power equipment. Report on the successful tests' passing in this laboratory is a confirmation of the high quality of the devices produced by Profotech.
