The disconnector comes from the Xiaokangjia series of terminal distribution boxes, with a unique humanized shape design, as the indoor lighting, sockets, electrical appliances overload, overvoltage, leakage short circuit protection, suitable for all kinds of civil residences, high-rise buildings, hotel buildings, shopping malls, hospitals, industrial and mining enterprises and other architectural occasions.
Disconnector routine maintenance method
1) Clean the dust on the surface of the porcelain, check whether the surface of the porcelain is glazed, damaged, whether there are cracks and flashover marks, and whether the iron and porcelain joint parts of the insulator are firm. If the damage is serious, it should be replaced;
2) Use gasoline to wipe the oil stain on the blade, contacts or fingers, check whether the contact surface is clean, whether there are mechanical damage, oxidation and overheating marks, twisting, deformation and other phenomena;
3) Check whether the accessories on the contacts or blades are complete and whether they are damaged; 4) Check whether the lead connecting the disconnector and the bus bar and circuit breaker is firm and whether there is overheating;
5) Check whether the soft connection parts are damaged, broken shares and other phenomena;
6) Check and clean the operating mechanism and transmission part, and add an appropriate amount of lubricating grease;
7) Check whether the distance between the transmission part and the live part meets the requirements; Whether the positioner and brake device are firm and the action is correct;
8) Check whether the base of the disconnector is good and whether the grounding is reliable.
1. What are the common faults?
Answer: The common faults of the disconnector are: (1) The contact part is overheated. (2) Porcelain insulation damage and flashover discharge. (3) Refuse to pull and close. (4) Incorrect pulling and closing.
2. What is the cause of overheating of the contact part of the disconnector during operation?
Answer: The disconnector overheats during operation, mainly caused by excessive load, increased contact resistance, and not fully closed during operation.
3. What are the reasons for the increase in the contact resistance of the disconnector?
Answer: The reason for the increase in contact resistance is: the repulsion at the contact between the blade and the knife tip is very large, and the knife edge is not tightly closed, resulting in surface oxidation, which increases the contact resistance. Secondly, the disconnector will cause arcing during the pulling and closing process, burn the contacts, and increase the contact resistance.
4. How to tell if the disconnector contact is overheating?
Answer: It can be judged according to the change of color change paint or temperature test sheet of the contact part of the disconnector, and can also be determined according to the darkening degree of the color of the blade. Now it is generally determined according to the infrared temperature measurement results.
5. How to deal with overheating of disconnector contacts and contacts?
Answer: When it is found that the disconnector contacts and contacts are overheated, first report the scheduling, try to reduce or transfer the load, strengthen monitoring, and then deal with it according to different wiring:
(1) Double busbar wiring. If the knife gate on the side of the busbar is overheated, the overheated disconnector will be taken out of operation through the inverted busbar and the power will be out-of-power.
(2) Single busbar wiring. Their load must be reduced, surveillance intensified, and measures taken to cool down, if conditions permit, to stop use as much as possible.
(3) Available bypass breaker with bypass circuit breaker inversion.
(4) If the line-side disconnector is overheated, the treatment method is basically the same as the single busbar treatment method, and the power outage maintenance should be arranged as soon as possible. During maintenance of operation, the load should be reduced and monitoring strengthened.
(5) Open-loop operation of one and a half circuit breaker wiring.
(6) For the overheating contacts and contacts of the busbar side disconnector, after pulling the disconnector, after on-site inspection, if the safety distance of live operation is met, the busbar side down lead joint can be electrolyzed, and then processed.
6. How to check and deal with the failure of the electric operation of the disconnector?
Answer: After the electric operation of the disconnector fails, first check whether there is any error in the operation, and then check whether the operation power circuit and power supply circuit are intact, and whether the fuse is blown or loose. Whether the electrical blocking circuit is normal.
7. How should the disconnector contact be welded deformed, the insulator is damaged, and the discharge is serious? A: When encountering these situations, the power should be cut off immediately, and the monitoring should be strengthened before the power outage.
8. How should the disconnector refuse to divide and close?
Answer: (1) Due to mechanical failures such as shaft pin falling off, wedge bolt exit, cast iron breakage, or because of electrical circuit failure, the cutter shank may be disconnected from the operating mechanism, resulting in the disconnector refusing to close, at this time the insulating rod should be used to operate, or in the case of ensuring personal safety, use the board hand to rotate the shaft of each phase disconnector switch.
(2) Refuse tripping. When the disconnector cannot be opened, if the operating mechanism is frozen by ice, it can be gently shaken, and the supporting porcelain bottle and the parts of the mechanism can be observed in order to find out the obstacle location according to where the deformation and displacement occur. If the obstacle location occurs in the contact part of the disconnector, it should not be forcibly pulled away, otherwise the support porcelain bottle may be damaged and cause a serious accident, at this time can only change the operation mode of the equipment to deal with it.
9. What should I do if the disconnector is not in place?
Answer: the disconnector is not in place, most of them are caused by mechanism rust, jamming, maintenance and debugging is not adjusted, etc., when this happens, the disconnector can be pulled open and then closed. For 220KV disconnector, it can be pushed in with an insulating rod, and if necessary, it should apply for power failure treatment.
The high-voltage disconnector should be overhauled 1-2 times every 2 years