Explosion proof switch box is an electrical equipment specifically designed for use in flammable and explosive environments. It is mainly used for distributing electricity and controlling electrical equipment, and can effectively prevent explosion accidents caused by sparks or high temperatures caused by electrical faults. Widely used in industries such as petroleum, chemical, coal mining, pharmaceuticals, metallurgy, shipbuilding, etc., suitable for explosive gas environments in Zone 1 and Zone 2, and combustible dust environments in Zones 20, 21, and 22.

A regular maintenance plan should be developed for the explosion-proof switch box (it is recommended to conduct small maintenance every month and major maintenance every quarter), with a focus on the explosion-proof structure, component status, and protective performance:

Monthly minor maintenance: basic inspection and cleaning

Appearance cleaning: Use a dry cloth to wipe the surface of the box to remove dust and oil stains. Do not use water or corrosive cleaning agents (such as alcohol, acid and alkali solutions); ​

Fastener inspection: Use a wrench to check the shell bolts and gland nuts one by one to ensure that they are not loose (increase inspection frequency in vibration environments, such as once every 10 days in coal mines and machinery factories); ​

Seal maintenance: Check if there are signs of aging (such as hardening or cracking) on the sealing strip. If there is slight aging, apply a special silicone maintenance agent. If there is severe aging, replace the explosion-proof seal with the same specification in a timely manner. ​

Quarterly maintenance: in-depth inspection and component maintenance

Internal cleaning: After turning off the power, open the box and use a dry brush or compressed air (pressure ≤ 0.3MPa, and keep away from the components to avoid blowing off the wiring) to clean the internal dust. It is forbidden to use a vacuum cleaner to directly absorb the components (which may generate static electricity); ​

Component testing: Use a multimeter to test the on/off performance of circuit breakers and contactors, as well as the contact resistance of wiring terminals (≤ 0.01 Ω, if the contact resistance is too high, it needs to be re tightened or replaced); ​

Grounding system inspection: Re check the grounding resistance (≤ 4 Ω). If the grounding resistance exceeds the standard, check whether the grounding main line is loose or corroded, and repair or replace the grounding cable in a timely manner. ​

Replacement of vulnerable parts: follow the principle of "same specification, explosion-proof type"

The replacement parts must be explosion-proof certified products: for example, circuit breakers and contactors need to be replaced with explosion-proof qualified products of the same model and specifications. It is forbidden to replace them with ordinary components (such as ordinary circuit breakers without explosion-proof structures, which will generate sparks when they fail); ​

Seal replacement: It should be consistent with the original specifications (such as size, material, nitrile rubber strip suitable for general environment, silicone rubber strip suitable for high temperature environment), and the sealing should be checked after replacement (after closing the box, press the joint with your hand, there should be no obvious gap); ​

Replacement record: Each time a component is replaced, the replacement time, component model, and reason for replacement should be recorded for easy traceability and maintenance history.