Explosion-proof positive pressure cabinet for dust workshop, inflatable explosion-proof electric control cabinet for starch and powdered sugar production line
We know that during normal operation, the explosion-proof positive pressure cabinet has a certain internal pressure, generally around 100 Pa, and is absolutely sealed from the outside atmosphere. During normal operation or full-load operation, the electrical appliances generate heat. Equipment aging and poor contact will cause electrical heating, and high external temperature will also cause the cabinet to heat up.
The consequences are: excessive heating will accelerate the aging of electrical appliances, affect their service life, and even burn out electrical components.
Therefore, general explosion-proof positive pressure cabinets must have strict requirements for their storage locations, and must also be used in conjunction with explosion-proof air conditioners. This creates a normal temperature working environment inside to allow the equipment to operate at its best.
1. When the air pressure is higher than 1000 Pa, the pressure relief valve will automatically open the exhaust valve and automatically adjust the internal air pressure to ensure that the product is not deformed or damaged by high air pressure impact.
2. When the air pressure is lower than 50 Pa, the automatic control system will automatically send out an alarm and output an alarm signal. The internal pressure needs to be adjusted. When the air supply is successful, it will automatically return to normal. Otherwise, the system can be set to automatically cut off the power if necessary (the national standard stipulates that the cabinet power supply must be cut off for low-pressure alarms in Zone 1, and the power supply does not need to be cut off for low-pressure alarms in Zone 2).
3. Only when the cabinet air pressure meets the specified air pressure requirements, the positive pressure purging control system will perform effective ventilation on the cabinet (Zone 1 needs to displace 7 times the free space of the cabinet, and Zone 2 needs to displace 5 times the free space of the cabinet). After the effective ventilation is completed, a signal will be sent to the cabinet to allow power supply.
4. The working air pressure inside the positive pressure cabinet is 50Pa≤P≤1000Pa.
Under the control of the automatic control system, protective gas is introduced, and the pressure in the positive pressure chamber is higher than the pressure outside the positive pressure chamber, forming a safe micro-positive pressure environment, thereby preventing flammable dangerous gases from entering the positive pressure chamber and ensuring the safe operation of the built-in ordinary instruments and electrical components. The automatic control system mainly completes a series of functions such as manual ventilation, air supply, automatic alarm and exhaust for overpressure, underpressure alarm, low-pressure interlocking power cut-off and so on. (This power distribution cabinet has a low-pressure interlocking function. When the air pressure is lower than the specified value (50 Pa), it will automatically cut off the user's power supply to the positive pressure chamber)
| Others | |
