Positive pressure compensation type explosion-proof power distribution cabinet, explosion-proof positive pressure cabinet

Explosion-proof positive pressure cabinet

Product Introduction

1. When the air pressure exceeds 1000Pa, the pressure relief valve will automatically open the exhaust valve to adjust the internal air pressure, so that the product will not be deformed or damaged by the impact of high air pressure.

2. When the air pressure is lower than 50Pa, the automatic control system will send out an alarm and output an alarm signal. It is necessary to adjust the internal pressure. When the air supply is successful, it will automatically return to normal. Otherwise, the system can be set to automatically power off if necessary (the national standard stipulates that the power supply of the cabinet must be cut off for low-pressure alarm in Zone 1, while the power supply does not need to be cut off for low-pressure alarm in Zone 2).

3. Only when the cabinet air pressure meets the specified air pressure requirements, the positive pressure purge control system will effectively ventilate the cabinet (Zone 1 needs to replace 7 times of the free space of the cabinet, and Zone 2 needs to replace 5 times of the free space of the cabinet). After the effective ventilation is completed, a signal will be sent to supply power to the cabinet.

4. The working air pressure inside the positive pressure cabinet is 50Pa ≤ P ≤ 1000Pa.

Scope of Application

1. Hazardous gas mixture locations: Zone 0, Zone 1, Zone 2.

2. Gas mixtures: ⅡA, ⅡB, ⅡC.

3. Temperature groups: T1 to T6.

4. Indoor and outdoor use (IP55)

5. Combustible dust environments: Zone 20, Zone 21, Zone 22

6. Corrosion protection grade: WF1

7. Suitable for hazardous environments such as petroleum and petrochemical, chemical, brewing, pharmaceutical, paint, textile, printing and dyeing industries;

Technical Parameters

1. Explosion-proof mark: ExpeIICT4;

2. Rated voltage: AC220/380V; Non-standard voltage: 12V/24V/36V/127V/660V;

3. Main switch current: 10A—40A;

4. Protection grade: IP54/IP55/IP65/IP66;

5. Thread specifications: DN15-DN100/G1/2-G4 inches

6. Lead-in wire specifications: diameter 6mm-80mm; Lead-out wire specifications: diameter 6mm-80mm;

7. Lead-in and lead-out directions: top-in top-out, bottom-in bottom-out (can be customized according to customer requirements without restrictions)

Functions of the Positive Pressure Purge Control System for Explosion-proof Positive Pressure Cabinets and Structural Features of the Cabinet Body

1. Its explosion-proof principle mainly adopts explosion-proof measures of isolating ignition sources with media and forming positive pressure protection to achieve the purpose of electrical explosion protection;

2. Structurally, it can be customized into box-type, console-type and cabinet-type structures according to user requirements. The cabinet-type structure is further divided into upper-lower structure and left-right structure. The box-type is generally welded with steel plates, with plastic spraying on the surface and front-door operation; the frame of the console-type and cabinet-type is welded with standard profiles, with plastic spraying on the surface, and each joint surface has undergone special sealing treatment; front-door operation and rear-door maintenance. The steel plate material is generally GB710-88 cold-rolled steel plate.

3. According to the air intake method, it is divided into continuous purge type and leakage compensation type. The continuous purge type provides uninterrupted and continuous air supply, and the working heat of the components installed in the positive pressure cavity can be taken away by the air path, with good heat dissipation function; the leakage compensation type provides intermittent air supply, the positive pressure cavity has good sealing performance, and the air consumption is small;

4. The positive pressure purge control system has complete protection devices. Power can only be automatically supplied after reaching the specified ventilation time. It also has safety interlock protections such as automatic sound and light alarms for high and low pressure, automatic power off when the pressure is below the limit, and automatic power off when opening the door, as well as emergency manual power off.

5. The sealing performance is reliable. The casing adopts multiple sealing protections, with long pressure holding time and operating cost saving.

6. This cabinet adopts the cable trench base installation form, and the user needs to provide protective gas source.

7. The product can be equipped with detection instruments, analysis instruments, display instruments, low-voltage electrical appliances, frequency converters, soft starters or computer control systems, and can be used as a central signal processing system and a central control system. During manufacturing, the user must provide a complete electrical system diagram and a material list for the control system.

8. Multiple cabinets can be connected in parallel.

9. Can be produced according to the electrical schematic diagram provided by the user.

10. The outer shell of this product is made of high-quality steel plate welding or stainless steel welding, and the surface is electrostatically sprayed with powder after high-speed shot blasting, with beautiful appearance;

11. The explosion-proof positive pressure cabinet consists of two parts: the cabinet body and the positive pressure purge control system device. The gas source of the explosion-proof positive pressure cabinet enters the cabinet through the positive pressure purge control device for purging to meet the safe air pressure requirements. When a low-pressure alarm occurs, the positive pressure purge control device will output an alarm signal, and the power supply of the positive pressure cabinet will be cut off if necessary.

12. Under the control of the positive pressure control system, the positive pressure cabinet is filled with protective gas, and the pressure in the positive pressure cavity is higher than the pressure outside the positive pressure cavity, forming a micro-positive pressure safe small environment, which prevents flammable hazardous gases from entering the positive pressure cavity, ensuring the safe operation of ordinary instruments and electrical components installed inside.

13. The automatic control system mainly completes high-end functions such as ventilation, air supply, automatic overpressure relief, low-pressure alarm and low-pressure interlock power off.