1. Prevent transformer overload operation. If the long-term overload operation, it will cause the coil heating, so that the insulation gradually aging, resulting in inter-box short circuit, phase-to-phase short circuit or short circuit to ground and the decomposition of the oil.
2. Ensure the quality of insulating oil. Transformer insulating oil in storage, transportation or operation and maintenance, if the oil quality is poor or impurities, too much water, will reduce the insulation strength. When the insulation strength is reduced to a certain value, the transformer will be short-circuited and cause sparks, arcs or dangerous temperatures. Therefore, the operation of the transformer should be regularly tested oil quality, unqualified oil should be replaced in a timely manner. The safety engineer site to add favorites
3. Prevent transformer core insulation aging damage. Core insulation aging or clamping bolt casing damage, the core will produce a large eddy current, resulting in long-term core heating caused by insulation aging.
4. Prevent maintenance inadvertently damage insulation. Transformer overhaul core, should pay attention to the protection of the coil or insulation casing, if found to have abrasion damage, should be dealt with in a timely manner.
5. Ensure that the wire contact is good. Poor contact within the coil joints, coil connection points, lead to the high and low voltage side of the casing of the contact point, as well as the tap changer on the pivot point of poor contact, will produce localized overheating, damage to the insulation, short circuit or disconnection occurs. At this time, the resulting high-temperature arc will make the insulating oil decomposition, producing a large amount of gas, the pressure inside the transformer plus. When the pressure exceeds the gas breaker protection value and not tripped, an explosion will occur.
6. Prevent electric shock. Power transformer power supply generally through the overhead line, and the overhead line is vulnerable to lightning strikes, the transformer will be burned due to breakdown of insulation.
7. Short circuit protection should be reliable. Transformer coil or load short-circuit, the transformer will be subject to considerable short-circuit current, if the protection system failure or protection value is too large, it is possible to burn the transformer. For this reason, must install a reliable short-circuit protection device.
8. Maintain good grounding. For the use of protection zero of the low-voltage system, the transformer low voltage side neutral point to be directly grounded when the three-phase load imbalance, the zero line will appear on the current. When this current is too large and the contact resistance is large, the grounding point will appear high temperature, igniting the surrounding combustible materials.
9. Prevent over-temperature. Transformer operation should be monitored for temperature changes. If the transformer coil wire is class A insulation, its insulator to paper and cotton yarn-based, high and low temperature on the insulation and service life of the great impact of the transformer insulation aging "six degrees of law", the transformer winding insulation temperature in the range of 90 ~ 130 ℃, the temperature rises 6 ℃, its insulation aging rate will be doubled, i.e., temperature Every 6 ℃, insulation life is reduced by 1/2. So when the transformer is running, must maintain good ventilation and cooling, if necessary, can be taken to take the forced ventilation, in order to achieve the purpose of reducing the temperature rise of the transformer.