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VTD 25 Voltage instrument transformers VTD 25 are single-phase transformers isolated with double-poles.They are designed for the use in the high voltage systems. They are designed for ...
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Voltage instrument transformers VTD 25 are single-phase transformers isolated with double-poles.They are designed for the use in the high voltage systems. They are designed for measuring and protection of high voltage distributing equipment for indoor design. The instruments can be provided with high voltage protectors protecting the surrounding distributing system.
The values of secondary voltage are 100, 110, 120 V. The accuracy classes for measuring winding are 0.2, 0.5, 1, for the securing winding is 3P or 6P. The transformers satisfy required accuracy class at intervals from 25% to 100% of rated load.
Transformers VTD 25 with fuses are provided with epoxy extenders, holders and fuse enclosures of type JT 6 (0.3 A or 0.6 A). Extenders with fuses can be dismounted.
Magnetic circuit of voltage transformers is made of oriented transformer strips in the shape of “C” of core.
All active parts of transformer are compound-insulated with epoxy-mixture. This material performs both the electrical insulating and the mechanical functions.
Transformers are fixed by the means of four screws M10 in the holes in the basic plate. The primary terminals of transformers are brought out by the means of nuts M10. We recommend use terminal ends corresponding to the used cross-section of the conductor for attaching to the secondary outlets.
The secondary terminal plate is provided with the cover with sealing screw. 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 mounting and operation”).
In cases where the substitution for the older types of transformers (various producers) is required, wesupply transformers VTD 25 with modified basic plates that have identical mounting spacing to spacing of thesubstituted types.
Voltage instrument transformers VTD 25 complied with all the tests according to ČSN EN 60044-2.
For the customer’s request we provide official calibration.