1、 Application scope of dust positive pressure explosion proof electrical control cabinet
1. This product is suitable for chemical industry, offshore drilling platform, metallurgy, medicine, light industry, textile, food, biological engineering, aerospace engineering and military industry and other explosive gas or dust environment. It is used as power supply for three-phase four wire system (380V / 220 V) AC low-voltage electrical distribution system or for detection instruments, analysis instruments, monitors, microcomputer touch screens, high-power frequency converters and other componentsMonitoring and control, heat dissipation, etc.
2. It is suitable for zone 1 and zone 2 dangerous places.
3. Suitable for IIA, IIB, IIC class, temperature group T1-T6 explosive gas environment.
4. Indoor and outdoor installation.
Picture of dust positive pressure explosion proof electrical control cabinet
2、 Explosion proof principle of dust positive pressure explosion proof electrical control cabinet
The explosion-proof measures of medium isolation ignition source are adopted.That is: the electrical components used by users are installed in a cabinet full of positive pressure clean gas, so that the flammable and explosive mixed gas in the external environment can not contact the electric spark or dangerous temperature produced by the electrical components in normal operation, so as to achieve the purpose of electrical explosion-proof.
3、 Product features of dust positive pressure explosion proof electrical control cabinet
It is composed of positive pressure distribution system and auxiliary power distribution system.
Front door, front door and back door are used for front door and back door.
3. Box type products adopt high-quality steel plate or stainless steel welding structure, the main and auxiliary plates are of upper and lower structure, hanging installation, lower incoming line, front door operation and maintenance.
4. High quality steel plate folding and welding is adopted for the piano table products. The main and auxiliary discs are of front and rear structure, with seat type installation, lower incoming line, piano table operation and rear door maintenance.
5. It can be divided into ventilation type and compensation type according to air intake mode.The ventilation type is continuous air supply, and the working heat of the components installed in the positive pressure chamber can be taken away with the gas path, which has a good heat dissipation function, which is suitable for solving the heat dissipation problem of high-power explosion-proof frequency converter; the compensation type is intermittent gas supply, and the positive pressure chamber should have good sealing performance to ensure low air consumption.
6. The user must provide gas source, the requirements are: purified air or nitrogen, the gas source pressure is 0.2 ~ 0.8MPa; generally, the instruments on the user's site can meet the requirements.
7. Steel plate material is generally gb710-88 cold rolled steel plate, and gb3280-84 stainless steel material can be selected according to user requirements.
4、 Function description of dust positive pressure explosion proof electrical control cabinet
1. The product is equipped with air exchange chain. Before the product is put into operation, only after the air exchange in the main disk cavity and reaching the specified air change time and volume, can the secondary panel be powered on by ensuring that the flammable and explosive gas is blown out of the main panel, and the air pressure in the main chamber is detected to ensure that the electrical components have been effectively isolated by clean media when the product is put into operation.
2. Only when the air pressure in the main panel meets the specified air pressure requirements, the automatic power supply switching system in the secondary panel will supply power to the main chamber.
3. The working pressure in the main panel is 100Pa ≤ P ≤ 1000Pa.
When the air pressure is higher than 1000Pa, the automatic control system will automatically close the air inlet or open the exhaust valve, and automatically adjust the internal air pressure to ensure that the product will not be deformed and damaged by the impact of high pressure.
When the air pressure is lower than 100Pa, the automatic control system will alarm automatically, open the air intake, and automatically adjust the internal air supply. When the air supply is successful, it will automatically return to normal, and the internal air pressure will drop to 60Pa. If necessary, the system can be automatically cut off.
4. The automatic control system of auxiliary panel is continuous monitoring, and displays the pressure parameters of main panel.
5. There are no restrictions on the manufacture of cabinet body and the internal components according to the requirements of customers.
The dust positive pressure explosion-proof electrical control cabinet is a kind of positive pressure explosion-proof cabinet specially designed for zone 2. Compared with PX series, PZ series omits the safety device for checking the air change time, and only marks the air change time, which is carried out by the user according to the requirements before the main chamber is powered on; in addition, when the internal air pressure is lower than 100Pa, the automatic control system will automatically alarm, open the air intake, and automatically adjust the internal air supply and air supplyWhen it is successful, it will return to normal automatically. When the internal gas drops to 50pA, the system will cut off power automatically and give an intermittent alarm.