What if there is condensation inside the central cabinet?

There are several methods to control the condensation of central cabinet: natural ventilation, forced ventilation (exhaust), electric heating, desiccant dehumidification and so on. , but the dehumidification effect is not ideal, the specific reasons are as follows:

1 Natural ventilation The natural ventilation method is mainly to optimize the foundation design of the ring network switchgear, prevent water vapor from entering the lower part of the cable room, raise the ground height of the ring network switchgear foundation, and install venetian blinds in the center of the foundation to make the internal and external air circulate effectively, reduce the internal humidity of the space below the ring network switchgear and prevent humid air from entering the cable room. It will not work when the environmental humidity is high, which will easily cause dust and pollution to enter and fail to achieve the purpose of moisture prevention.

2. Forced ventilation/air exchange method Forced ventilation/air exchange method is to install an exhaust fan at the bottom of the box cabinet and an exhaust fan at the top side to accelerate the air circulation in the cabinet, so that the air in the cabinet is always in an unsaturated state and the conditions for condensation formation are destroyed. The disadvantage is that this method needs to be equipped with fans and other equipment, which will produce noise during operation. At the same time, some cabinets have limited internal space and are difficult to install.

3. The electric heating method is to install aluminum alloy heaters (generally 150W) in the cable room and circuit breaker room below the cabinet to increase the gas temperature in the cabinet, reduce the relative humidity and prevent condensation. However, due to the lax sealing in the box, the heated steam can not be discharged out of the box in time, which will make the condensation place more and more serious, and the place with less condensation will also increase the condensation speed. In the long run, it will cause serious consequences, such as corrosion and mildew of cables and terminal boards, and the service life of equipment will be greatly reduced. In serious cases, it will cause short circuit and misoperation of equipment. For the terminal box of substation with serious dew condensation, water drops may drop on the terminal, resulting in grounding fault.

4. The desiccant method is simple and easy to use, that is, the desiccant is used to absorb the moisture in the cabinet to avoid the formation of condensation. However, in practical use, due to its limited water absorption effect, it is difficult to discharge the absorbed water, and the effect is often not obvious, which increases the maintenance workload.

For long-term and effective methods to deal with the moisture in the cabinet, many methods adopted by major substations at present are to install intelligent dehumidifiers in the cabinet, such as SEPRI-CS-NL(E) anti-condensation device and SPR-CN-S 1 intelligent dehumidifier, which are small in size and can discharge the moisture in the cabinet through hoses. It can also dehumidify at low temperature. Realize automation, when the humidity in the cabinet exceeds the standard, it will work automatically.