Aug 19

The intelligent control variable frequency positive pressure cabinet is integrated with HMI, PLC and frequency converter. It can realize the frequency conversion control mode of the mud centrifuge, which makes the operation more humanized. The customer can select different speed and difference speed according to the material conditions on site.

 

The automatic control makes the equipment more widely applicable to the site. The customer sets the centrifuge main engine speed 0-3200r/min according to different materials, and the differential speed is adjusted at 10-45r/min. The state screen automatically reminds the centrifuge maintenance parts to be regularly maintained. The alarm compensates for the damage caused by the negligence of the staff; the alarm screen shows the fault alarm when the electrical equipment has a problem, and the user can better find the problem in time.

PLC smart control VFD centrifuge

PLC smart control VFD centrifuge

Positive pressure control cabinet operation has more clean instrument air than previous explosion-proof frequency conversion cabinets. For most customers, it seems more troublesome than the explosion-proof control cabinet. It is more reasonable from the following points:

  1. Performance and heat dissipation of the inverter (take ABB inverter as an example)

Because of the working principle, the inverter needs to dissipate a large amount of heat during normal operation. Under normal circumstances, the inverter works best at a constant temperature (generally 40-50 °c). How is this heat in a closed space? In order to pass, there are usually two ways; a) heat exchange b) cooling by the outside world.

 

A), explosion-proof inverter for heat exchange:

 

Explosion-proof inverter

B), positive pressure ventilation type control cabinet

 

Positive pressure ventilation type control cabinet

 

  1. We are in terms of explosion-proof performance
  2. A) Explosion-proof type explosion-proof:

 

In the case of this explosion-proof mode, the explosive gas can enter the casing, but the flame gas cannot propagate to the outside through the joint surface in the event of an explosion, that is, the explosion-proof body can prevent the flame in the box from spreading outward after the explosion, but Explosion inside the cabinet can damage the components and is also a loss.

 

B), positive pressure type explosion-proof control cabinet

 

Through this method, the pressure of the internal instrument to enter the clean instrument gas is higher than the outside, that is, the pressure inside the box is higher than that outside the box, and the explosive mixture of the outside can not enter the tank or the concentration of the explosive gas entering the explosion limit. , so there will be no bad explosion at all.

 

The total positive pressure explosion-proof control cabinet seems to be more troublesome than the explosion-proof control cabinet, but it is safe and reasonable.

Engineers can choose according to different equipment use site requirements

More question,welcome contact GN solids control

written by admin


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