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Oil-immersed transformer manufacturers teach you the correct way to sample transformer oil

Oil-immersed transformer manufacturers are familiar with transformer oil sampling because it is a must for routine maintenance of oil-immersed transformers. However, many distribution transformer maintenance personnel are not professional and there are problems with the sampling method. Sampling should be carried out on a dry, sunny day. The container and sampling method used for sampling have the most direct impact on whether the actual quality of the oil can be truly reflected. The oil sample for the pressure test shall not be less than 0.5 kg, and the oil sample for the simplified test shall not be less than 1 kg. The sampling container is a colorless glass bottle with a wide-mouth frosted glass plug of 0.5 kg or 1 kg capacity. Two to three bottles should be taken at a time for analysis and testing. Label the sample with the name, source, date of sampling, sampler, weather conditions and other information.

Before using the sampling container, it should be washed with gasoline, soap liquid or other degreasing solvent (such as trisodium phosphate), then rinsed with water until it is not alkaline and can be evenly flowed from the bottle wall with water. Finally, it was washed several times with distilled water. The cleaned sampling container is placed in an oven at 105 ° C. After cooling, the stopper is tightly closed and must not be opened before use. After sampling, use a clean paper or cloth to wrap the glass stopper firmly to prevent dirt and moisture from smearing the bottle. Outdoor sampling should be carried out in sunny weather or in dry weather with low humidity. When sampling, it should be protected from rain, snow or dust. The oil in the oil storage equipment should be allowed to stand for more than 8 hours before sampling; if it is sampled in the oil-immersed distribution transformer in operation, it does not need to be left standing. Before and after sampling, apply a clean or no fine cloth to clean the area around the sampling port.
Oil-immersed transformer manufacturers
When taking the oil sample of the oil-immersed power transformer in operation, the oil drain valve or the sampling valve at the lower part of the fuel tank should be released about 2kg of the accumulated oil at the bottom to clean the oil drain hole, and then take the oil sample. When a new oil supplemented by a transformer and a freshly filtered oil sample are taken, the oil sample should be taken after sufficient standing. When sampling from a small transformer without a drain pipe (or oil sample valve), it can be inserted into the transformer with a glass tube or the like when it is not in operation to extract the oil sample at the bottom, or the oil change method can be used instead of sampling the fuel tank. In the middle sampling, after opening the lid, insert the washed and dried glass tube into the oil, and press the nozzle with the thumb. After inserting the person, release the thumb, let the oil enter the tube, and then press it with the thumb. The tube is raised by a tube, and while rotating, the oil in the tube is discharged to wash the sampling tube, and this is repeated twice, and then the oil sample is aspirated.

ZTELEC--a professional oil-immersed transformer manufacturer with strict testing and good quality.

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