How to maintain the voltage stabilizer

1.Strengthen daily inspections, maintenance and regular testing

Key inspection contents include:

(1) Look at the appearance. Mainly check whether there is oil leakage on the outside of the voltage regulator, whether there is smoke or discharge from the components. The voltage stabilizer may leak oil due to loose welding of the voltage stabilizer shell or loose rubber pads. If the oil level is too low, the insulation protection will be lost, resulting in discharge between the conductive parts or between the conductive parts and the shell. In severe cases, the voltage stabilizer will be burned. Therefore, the fault should be eliminated and the oil should be replenished in time to ensure that the oil level is maintained at 1/4-3/4 of the oil mark. For loose parts, poor contact or even discharge, the voltage stabilizer drop fuse should be disconnected in time to eliminate hidden dangers.

(2) Listen to the sound. A normally operating voltage stabilizer will emit a uniform and subtle buzzing sound. When the voltage stabilizer has a fault of different nature, the sound will change. At this time, measures should be taken according to the on-site situation to find the cause of the fault.

(3) Check the oil stains on the distribution transformer and the dust on the high and low voltage bushings, and clean and wipe off the oil stains and dust in time to prevent flashover discharge in humid or rainy weather, which may cause short circuit between bushings, blow the high voltage fuse, and make the distribution transformer unable to operate normally. We require the inspectors to clean at least once every two months.

(4) Observe the oil color and regularly check the oil temperature, especially in weather with large load changes, large temperature differences, and bad weather, increase the number of inspections, and the top oil temperature of the oil-immersed distribution stabilizer during operation shall not be higher than 95℃. To prevent the winding and oil from deteriorating too quickly, the temperature rise of the top oil should not often exceed 45℃.

(5) Shake and measure the insulation resistance of the distribution transformer, and check whether each lead is firm. Pay special attention to whether the low voltage outlet connection is in good contact and whether the temperature is abnormal.

(6) Strengthen the measurement of power load. During the peak period of power consumption, strengthen the load measurement of each distribution transformer. If necessary, increase the number of measurements and adjust the distribution voltage stabilizer with unbalanced three-phase current in time to prevent the neutral line current from burning out the lead, causing damage to user equipment and distribution transformer. For distribution transformers with connection group Yyn0, the three-phase load should be as balanced as possible. Only one or two phases should not be used for power supply. The neutral line current should not exceed 25% of the rated current on the low-voltage side. Strive to ensure that the distribution transformer is not overloaded or unbalanced.

(7) Regularly check and replace primary and secondary fuses. It is strictly forbidden to use aluminum wire instead of fuses. As we all know, the primary fuse protects the system and the secondary fuse protects the voltage stabilizer. The fuse selection must be adapted to the voltage stabilizer capacity.

2. Prevent external force damage:

(1) Reasonably select the installation location of the distribution transformer. The installation location should be as close to the load center as possible, and the power supply radius should be controlled within 0.5km. At the same time, try to avoid installing it in areas prone to lightning strikes or low-lying waterlogging areas. Because it is located in the county town, there are many voltage stabilizers at the intersection. In order to reduce the accidents of cars hitting the pole towers, anti-collision strips are pasted on all the pole towers along the road.

(2) Try to avoid installing low-voltage meter boxes on the distribution voltage stabilizers. Due to long-term operation, the glass of the meter box is damaged or the low-voltage pile head of the distribution transformer is damaged and cannot be replaced in time, resulting in the burning of the power meter due to rain and other reasons, causing damage to the distribution transformer. More than 95% of the public distribution transformers in our institute are all installed with JP cabinets, which play a good role in protecting the safe operation of the voltage stabilizer.

(3) It is not allowed to adjust the tap switch privately to prevent the tap switch from being adjusted in place and causing phase short circuit, which will burn the distribution voltage stabilizer.

(4) Install insulation covers on the high and low voltage ends of the distribution transformer to prevent natural disasters and external damage. Install high and low voltage insulation covers in residential areas with narrow roads and forest areas where animals frequently enter and exit to prevent objects from falling on the distribution voltage stabilizer wiring piles and causing low voltage short circuits and burning the distribution transformer.

(5) Regularly inspect the lines and cut down line channels to prevent tree branches from hitting the wires and causing low-voltage short circuits that could burn out the distribution stabilizers.