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  • What are the factors that affect the insulation strength of SF6 gas?

    There are the following factors influencing the insulation strength of SF6 gas.
    1. The effect of uniform electric field performance. Under a uniform electric field, the insulation strength increases linearly with the distance between the contacts. If the distance is too large, duo to the uneven state of the electric filed, the insulation strength increases and saturation occurs. Under an uneven electric field, its insulation strength will even approach the air level.
    2. The relationship with stress. The insulation strength increases with the increase of gas pressure. Under the more uniform electric field, the insulation strength is affected by the thickness of vessel wall and the volume of components inside the equipment.Don't raise the gas pressure too high.Generally at 20℃, the pressure of SF6 gas chamber is 0.3~ 0.6mpa, and that of SF6 arcing chamber is 0.5~ 0.7mpa.
    3. Influence of electrode surface state. Generally, the rougher the electrode surface, the lower the breakdown voltage.The greater the electrode area is, the greater the probability of the occurrence of accidental factors will be, thus reducing the breakdown voltage
    Influence of voltage polarity. As the insulation structure of SF6 circuit breaker is in the form of slightly uneven electric field, the insulation level is often determined by the complex polarity voltage.
  • Why we need GDRZ-902 Transformer SFRA

    After the transformer is designed and manufactured, its coil and internal structure are determined. Therefore, for a multi-winding transformer coil, if the voltage level is the same and the winding method is the same, the corresponding parameters (Ci, Li) of each coil should be Is ok. Therefore, the frequency domain characteristic response of each coil is also determined accordingly, and the frequency spectrum of the corresponding three-phase coils is comparable.


    Transformer is an indispensable important instrument in power system. During transformer repair or transportation, transformer winding may be deformed. At the same time, inter-turn and inter-phase short circuit may also occur during the test of transformer. The transformer winding deformation tester is mainly used to measure various parameters of the transformer internal winding. After obtaining various accurate measurement data, the computer system compares and analyzes it to make judgments on the internal fault state of the transformer.

  • What kind of certificate can you provide?

    We can provide CE mark,ISO 9001 quality certificate, the third party calibration certificate(CNAS),factory test report.
  • What's the delivery lead time?

    For most of the products, delivery lead time is 10 days after the order is confirmed; For some customized products, please check with the sales person.
  • What's the payment term?

    For total amount below USD3,000.0, payment term is 100% T/T as deposit; For total amount above USD3,000.0, payment term is 30% T/T as deposit, the balance before delivery; The payment term is also negotiable.
  • What's the warranty period?

    Warranty period is 1 year



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