The explosion-proof positive pressure box forms a certain positive pressure environment inside the box by filling it with clean and dry protective gas (such as compressed air). When the pressure inside the box reaches the set value (usually within the range of 50 - 1000Pa), the positive pressure inside the box can prevent dangerous explosive gases, dust, etc. from the outside from entering the box.

During the operation, the intelligent control system and the pressure control system play a key role. The intelligent control system is responsible for monitoring the pressure conditions inside and outside the box, gas flow and other parameters, and controlling and regulating the intake and exhaust. When the pressure inside the box is lower than the set lower limit (such as 50Pa), the control system will send out an alarm signal and may trigger the gas replenishment operation to maintain the positive pressure state inside the box; when the pressure exceeds the set upper limit (such as 1000Pa), the pressure relief valve will automatically open to discharge the excess gas to ensure that the pressure inside the box is within the safe range.

In addition, before introducing electrical equipment into the box, the positive pressure purging control system will carry out gas replacement in the box to remove the potentially remaining dangerous gases or impurities. When the replacement meets the specified requirements (for example, in Zone 1, 7 times of the free space of the cabinet needs to be replaced, and in Zone 2, 5 times of the free space of the cabinet needs to be replaced), the system allows the electrical equipment to be powered on and operate, so as to ensure that the inside of the box is always in a safe positive pressure explosion-proof state throughout the operation process.