Power transformer installation precautions
Power Transformer installation precautions
1. Reasonable selection of the installation location of the distribution transformer The installation of the distribution transformer must meet the requirements of the user's voltage, and try to avoid installing the distribution transformer in the barren hills, which is vulnerable to lightning strikes and away from the residential area. The maintenance personnel are regularly maintained and it is not convenient for staff management.
2. Reasonable selection of the capacity of the distribution transformer It is also very important to choose the capacity of the distribution transformer. It can neither cause overloading of the distribution transformer, nor can it cause waste of the big horse-drawn car. According to the user load situation, the capacity should be counted and the distribution transformer capacity should be reasonably selected. Such as: a 100kV ̇A distribution transformer, with a power factor of 0.85, it can carry 85kW load.
3. Strengthening the measurement of power load During the peak period of power load, the load of each distribution transformer should be strengthened. If necessary, increase the number of measurements. The distribution transformer with unbalanced three-phase current should be adjusted in time to prevent neutrality. If the line current is too large, it is easy to burn the lead and cause the user equipment to burn out.
4. Avoid installing low-voltage metering boxes on distribution transformers. The low-voltage metering boxes installed on the distribution transformers in remote mountainous areas should be gradually removed, and replaced as indoors as much as possible.
In order to facilitate management and prevent power loss, low-voltage metering boxes are installed in remote mountainous areas. Due to long-term operation, the glass of the measuring box is damaged or the low-voltage pile head of the distribution transformer cannot be replaced in time, causing the electric energy meter to be burned due to rain or the like. The electrical transformer is damaged.
5, reasonable allocation of distribution transformer high and low voltage fuses melt distribution transformer high and low voltage fuse melt configuration is unreasonable, easily causing serious overload of the distribution transformer and burning distribution transformer. High and low pressure melt configurations should follow:
1） The transformer with a capacity below 100kV ̇A is equipped with a fuse body with a rated current of 2.0 to 3.0 times; 2 for a transformer with a capacity of 100kV ̇A or more with a melt of 1.5 to 2.0 times the rated current; 3 for the low-voltage side fuse according to the rated current Slightly larger configuration.
6. It is not advisable to adjust the tap changer privately. Because of the difference in power load between winter and summer, the voltage level is slightly different. In order to meet the voltage demand, some rural electricians randomly adjust the tap changer without performing related tests, resulting in the tap changer not being in place. , causing a phase-to-phase short circuit to burn out the distribution transformer.
7. The distribution transformer is equipped with insulation cover to prevent natural disasters and external damage. If necessary, install high and low voltage insulation covers for the narrow roads and forest protection areas to prevent the low voltage short circuit from burning the transformer on the distribution transformer.
8. The lightning arrester should be installed on the high and low voltage sides of the distribution transformer. The lightning arrester should be installed on the high and low distribution transformers in the multi-mine area. If the quality of the arrester is not qualified or the fault is not replaced in time, it is easy to be attacked by lightning.
During the thunderstorm season, the arrester should be sent to the repair department for testing and timely installation. It is forbidden to use unqualified products.
9. Regularly measure the grounding resistance of the distribution transformer. After long-term operation (especially the grounding lead is replaced by aluminum wire), the distribution transformer will be severely oxidized, the grounding resistance will increase, and the grounding body will be corroded and broken, resulting in a neutral point potential. Offset.
When lightning strikes or overvoltage, it is easy to cause an accident. According to the regulations, the grounding device should meet: the grounding resistance of the distribution transformer below 100kV ̇A is not more than 10Ω, and the grounding resistance of the distribution transformer above 100kV ̇A is not more than 4Ω.
10. Strengthen the daily management of regular inspection routes, cut down trees, and prevent branches from hitting the wires causing low-voltage short-circuit to burn the distribution transformer. The lack of daily management of the distribution transformer by the staff makes the transformer run out of oil for a long time. The end of the respirator is installed or the silica gel is not replaced in time, so that the distribution transformer is flooded.
It is easy to cause an accident. There are quality problems in the distribution transformer itself. Because the installation location of the distribution transformer is far away, some construction personnel arbitrarily put the untested distribution transformer into operation, temporarily using electricity, and burning the transformer.
11. Regularly check the low-voltage lead wires of the distribution transformer. It is strictly forbidden to use the wire itself to make the wire nose. It should be directly connected to the low-voltage pile head of the distribution transformer. Regularly check and strengthen the joint between the lead wire and the distribution transformer pile head to prevent the burning of the distribution due to loosening. Low voltage pile head of electric transformer.
In order to make the distribution transformer run safely for a long time, and there is less failure, as the operation management personnel, it is necessary to do diligent inspection, diligent maintenance, and diligent measurement, timely find problems and deal with them in time to avoid the expansion of the fault and burn out the distribution transformer.