Views: 22 Author: Site Editor Publish Time: 2021-05-15 Origin: Site
The regular maintenance of the distribution box is to check and clean the distribution device regularly; the action flexibility of the operating mechanism and the opening and closing of the auxiliary contact should be correct; the performance and fixation of all electrical components and accessories should also be checked; the metal bus bar and terminal block should be checked to prevent electrochemical corrosion and the deformation of the bus bar after being pressed; the column grounding device should be checked regularly to see if it is in good condition; the check is not correct The lines in the moving contact and the fixed contact shall be consistent, the contact shall be in close contact and sufficient pressure shall be ensured.
The daily maintenance of the distribution box should pay attention to cleaning the inside and outside of the distribution device; check the porcelain bushing, all kinds of electrical connectors and buses; check whether the connection of each device is good; pay close attention to the display of the instrument and whether all kinds of electrical connectors are overheated.
Distribution box in the process of operation and use, as long as in accordance with the safety operation rules to operate, regular maintenance and daily maintenance of the distribution box can maintain a good working condition, reduce the probability of safety accidents.
(1) The function of preventing the high-voltage distribution cabinet from entering the live space by mistake makes the opening and closing of the switch cabinet door have a locking relationship with the grounding switch, that is, the switch cabinet door can only be opened after the grounding switch is closed. This accident exposed the imperfection of the "five prevention" Mechanical locking device of the old high-voltage switch cabinet.
(2) Neon lamp brightness is low, especially in the bright environment, brightness is washed, poor display.
(3) The old-fashioned high-voltage live display device with forced electrical locking has too simple locking principle, which only combines the output signals of a, B and C three-phase sensors after half wave rectification to control the locking circuit. In this way, when single-phase grounding or lack of phase occurs in the system, the floating of blocking control voltage can lead to the failure of reliable locking of the device, resulting in the accident of live closing of grounding switch.
(4) At present, the neon lamp type high-voltage live display device is mostly installed in the high-voltage equipment compartment with plastic shell. Once the switch cabinet is short circuited and arced in the operation process, the high-temperature arc may melt the plastic shell of the device and hurt the operation or maintenance personnel.
(5) Power test of high voltage distribution cabinet is a problem that has puzzled power safety production for many years. At present, the mechanical "five prevention" locking device of fully enclosed "five prevention" switch cabinet can not meet the requirements of "prior electricity and hanging grounding wire" in safety regulations. Because in the implementation of power failure work, before closing the grounding switch, it must be verified that the equipment has no voltage. However, the enclosed high-voltage switchgear is in a fully closed state. According to the normal operation method, it is impossible to use the portable high-voltage electroscope to test the electricity of the equipment. Therefore, there is a way of forcibly unlocking and opening the door of the switchgear to test the electricity.
(6) At present, high voltage live display devices with neon lamps as display elements are widely used in power distribution cabinets. After a long period of operation, it is found that the blindness rate is high and neon bubbles are damaged. In order to make up for the defects, a neon lamp running / closing switch is installed on the live display device, which is usually closed, so that the whole high-voltage live display device is temporarily out of operation. In this way, the high-voltage live display device is no longer used to monitor whether the line side is live or not.