Advantages of oil-immersed test transformers

Oil-immersed test transformers are widely used in power systems, industrial and mining enterprises and other departments. Oil-immersed test transformers of the same type include gas-filled test transformers and dry-type test transformers. Let’s take a look at the advantages and disadvantages of oil-immersed transformers.

Advantages and disadvantages of oil-immersed test transformers

Compared with the same type of oil-immersed test transformer, its internal windings are exactly the same, the difference is that the insulating material or medium is different. Dry-type transformers are insulated by epoxy resin. The advantage is that they are lighter, but the voltage is limited, and the maximum voltage is only 120kV. In addition, the epoxy resin is easy to break after impact, and the gas-filled transformer is insulated with SF6 gas, which has high precision, high voltage, light weight and relatively expensive price. Generally used by the Metrology Institute and Inspection Institute as the standard voltage. In addition to shortcomings, oil-immersed test transformers also have many advantages.

Oil-immersed test transformers use oil as the insulating medium, which has the characteristics of high voltage, large capacity, metal shell and durable shell. Under the same capacity, the price is much cheaper. In addition, maintenance of oil-immersed transformers is cheap and quick. Once the cable package fails, you only need to unscrew the shell screws, remove the insulating oil, replace the cable package with a new one and inject new oil. Compared with dry-type and gas-filled test transformers, oil-immersed test transformers are more convenient, and the speed of transformer inspection is much faster.

The advantages of oil-immersed test transformers outweigh the disadvantages. If there are no special technical requirements, we recommend that you choose an oil-immersed test transformer, which is cheap, sturdy and durable. Although it is heavier than the same type of product, the weight range is not obvious in the case of small capacity, such as 5KVA.

Oil-immersed transformer cable withstand voltage test instructions

This depends on the cable length, cross-sectional area and test voltage. For example, 5K test transformer is used for 10kV cable withstand voltage, and the length shall not exceed 5m. This can be calculated with data. The 10kV cable is calculated at 1.5A per kilometer, and the maximum current of a 5K/50kV test transformer is only 1000mA. Of cHV Hipot Electric Co., Ltd.se, you can also choose a larger capacity oil-immersed test transformer.