Bus ducts are usually located on the underground floors of shopping malls.Many people say what to do if there is water ingress.Air type bus ducts do not require special treatment for water ingress,only the water needs to be controlled dry.Check if there are any foreign objects inside the slot and clean it thoroughly to avoid any power leaks or short circuits.The first thing to consider when it comes to water ingress in dense bus ducts is the protection level of your bus duct.If the protection level is high,a small amount of water may not cause much damage to it.If the protection level is low,the water must be cleaned before use,otherwise a short circuit may occur.The protection level is the IP address,such as IP65.The larger the number,the higher its dust and water resistance.

　　If the protection level is low,go directly to the manufacturer and test the resistance between each section of the busbar and the phase to shell.If any section is not within the specified range,it must be replaced completely because it is difficult to dry.The replacement price is estimated to be around 30%-40%of your original busbar slot price.Bus ducts are generally designed for indoor use,and the humidity in the air does not affect the operation of the bus ducts.However,if water enters the bus ducts during use,it will inevitably cause insulation reduction,and long-term operation will cause short circuits and burn out the bus ducts.Therefore,necessary protective measures should be taken for installation methods that may cause water ingress into the bus duct.When the bus duct passes through a floor,due to various reasons such as production or roof leakage,water accumulates on the floor,which will leak down along the bus duct passing through the floor,causing water to enter the bus duct and reducing its insulation.

　　The insulation resistance value of the bus duct is related to the length of the bus duct,the humidity and temperature of the surrounding environment.When measuring the insulation resistance of low-voltage bus ducts,a 500V insulation resistance meter can be used,which generally cannot be lower than 0.5MΩ.Domestic bus duct manufacturers stipulate that the insulation resistance of each unit's bus duct should not be less than 20MΩ,usually reaching 500MΩ.After installing the bus duct,conduct a detailed inspection and use a feeler gauge to check the gaps at the connection points.No metal or other objects are allowed to remain on the bus to prevent short circuit accidents.Using an insulation resistance meter for insulation shake testing,the insulation resistance of the busbar is greater than 0.5MΩ.The method of measuring the resistance of bus duct using a megohmmeter should be selected correctly according to the voltage level of the equipment.For equipment below 500V,a 500V megohmmeter should be selected;Equipment above 1000V should be equipped with shaking meters of 1000V and 2500V respectively to prevent accidents caused by incorrect selection.When using the shaking table,it should be placed steadily and the shaking table speed should be controlled reasonably.Avoid sudden changes in speed,and generally control the speed at 120 revolutions per minute.

　　It is strictly prohibited to measure live bus ducts.The power supply of the equipment must be cut off first,isolated from the power supply,and necessary short-circuit grounding must be carried out.A single stranded wire with insulation material should be used to connect the busbar copper bar and the shaker.Before formal measurement,the shaking table device should be checked for normal operation,and an open circuit test and a short circuit test should be conducted separately.The insulation resistance value varies with the length of measurement time,and is generally measured after 1 minute.For equipment with particularly large capacitance such as bus ducts,the reading should be based on the stable pointer.