1. Sampling should be carried out on a dry and sunny day. The oil sample for pressure test should be controlled at more than 0.5kg, and the oil sample for simplified test should be controlled at more than 1kg;
2. The sampling container is a colorless glass bottle with a sand glass stopper with a capacity of 0.5 kg or 1 kg. Collect 2-3 bottles at a time for analysis and testing. Labels should be affixed when sampling, pay attention to the name of the oil sample, source, sampling date, sampler, weather conditions and other information;
3. Before using the sampling container, please clean it with gasoline, soapy liquid or other solvents to remove oil stains to make it non-alkaline. Rinse it with clean water until the used water flows down evenly from the wall of the bottle. Then wash it several times with distilled water. The cleaned sampling container is dried in an oven at 105 degrees, and the stopper is closed after cooling, and do not open before use;
4. After collection, wrap the glass stopper firmly with clean paper and cloth to prevent dirt and moisture from soiling the bottle mouth;
5. Outdoor sampling should be carried out on sunny days or dry weather with low humidity, and the intrusion of rain, snow and other garbage should be strictly prevented when sampling;
6. The oil in the oil storage equipment should usually be allowed to stand for more than 8 hours before sampling. If sampling is performed in a transformer in operation, there is no need to stand still;
7. Before and after sampling, use a clean or lint-free muslin to wipe clean around the sampling port;
8. When collecting oil samples of the transformer in operation, please drain about 2kg of sewage accumulated at the bottom from the drain valve or sampling valve at the bottom of the oil tank, and then collect the oil sample after cleaning the drain;
9. When collecting new oil supplemented from the transformer and freshly filtered oil samples, please stand still before collecting oil samples;
10. When sampling from a small transformer without a drain pipe (or sliding throttle), a glass tube can be inserted into the transformer when it is not working, and the oil sample at the bottom can be taken, or the oil change method can be used instead of sampling;
11. When extracting from the tank, after opening the lid, insert a clean and dry glass tube into the oil, while pressing the nozzle with your thumb, loosen your thumb, put the oil into the tube, and press it with your big finger Hold the mouth of the tube, lift the glass tube, rotate it while oil is in the tube, to clean the sampling tube, and use it after 2 cycles;
12. When sampling in batch oil drums, samples must be selected based on 5% of the total number of oil drums, but not less than 2 drums. To use small buckets or whole bottles for sampling, sampling must be performed at 2% of the total number of buckets (bottles);
13. When taking oil samples, you must strictly abide by the on-site safety and fire protection regulations.