Special transformer VTDO 38

Voltage instrument transformers VTDO 38 are single-phase transformers isolated with double-poles. They are designed for the use in the high voltage systems from 3.6 kV to 38.5 kV. They are designed for measuring and protection of high voltage distributing equipment for outdoor design. They are suitable for supplying of drives of remote-controlled section switches.

The values of secondary voltage are 100, 110, 120 V. The accuracy classes for measuring winding are 0.2, 0.5, 1, 3. The transformers satisfy required accuracy class at intervals from 25% to 100% of rated load.

Voltage instrument transformers VTDO 38 are single-phase transformers isolated with double-poles. They are designed for the use in the high voltage systems from 3.6 kV to 38.5 kV. They are designed for measuring and protection of high voltage distributing equipment for outdoor design. They are suitable for supplying of drives of remote-controlled section switches.

The values of secondary voltage are 100, 110, 120 V. The accuracy classes for measuring winding are 0.2, 0.5, 1, 3. The transformers satisfy required accuracy class at intervals from 25% to 100% of rated load.

Magnetic circuit of voltage transformers VPT 38 is made of oriented transformer strips in the shape of 'C' of core./p>

All active parts of transformer are compound-insulated with epoxy-mixture resistant to the external effects (UV radiation, humidity, etc.). This material performs both the electrical insulating and the mechanical functions.

Transformers are fixed by the means of four screws M12 in the holes in the basic frame. The outlets of primary windings 'A' and 'B' are brought out by the means of bolts M10. For contacting them we recommend use conductors of maximum diameter of 6 mm2 and terminal ends by reason of suspension of dynamic forces and vibrations within the system.

ATTENTION! The isolators must not be pre-stressed mechanically in the direction away from the body of transformer during the other way of contacting.

We recommend use terminal ends corresponding to the used cross-section of the conductor for attaching to the secondary outlets. The secondary terminal board is covered with the waterproof cover. It is possible to seal the cover. Inside, there is the set with jumpers and small screws for the possibility of earth connection and short circuiting of the wiring. (See 'The Instructions for the operation and mounting').

In cases where the substitution for the older types of transformers (various producers) is required, we supply transformers VTDO 38 with modified basic plates that have identical mounting spacing to spacing of the sub-stituted types.

Voltage instrument transformers VTDO 38 complied with all the tests according to IEC 60044-2.

For the customer’s request we provide official calibration.

It is possible to consult other technical parameters with the producer.

Highest voltage for equipment: 36/38.5 kV
Power frequency test voltage: 70/80 kV
Lightning impulse test voltage: 170/180 kV
Nominal primary voltage: 6000 – 22000 V
Nominal secondary current: 100, 110, 120,230 V
Short-circuit voltage: 4.5%
Max power: 2000 VA
Nominal frequency: 50 Hz
Weight: 62 kg
Thermal insulation class: E
Operation conditions: 

operating temperature from -40 to + 40 °C

corresponds to temperature class -40 / 40 according to IEC 61869-1

Standard: ČSN EN 60044-2, IEC EN 60044-2, ČSN EN 61869-1, ČSN EN 61869-3, IEC EN 61869-1, IEC EN 61869-3, GOST 15 150