General information of protection type pressurized Ex p      

In modern chemical plants increase the need of complex electrical equipment used in the processing area of flammable materials. An explosion protection of electrical equipment will be ever higher requirements. The ignition pressure encapsulation EEx p offers a variety of applications.

The overpressure encapsulation (ex-p) makes it possible to use not explosion-proof equipment in hazardous areas. The overpressure encapsulation is the idea, to keep away explosive gas from the non-ex-devices.






                        

                           

    For all Non Ex devices and controlsystems
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Principal of pressurized ( purge) systems

Principal of the pressurized system

The explosion protection by pressurized system is realized by using the non-explosion devices in a overpressurized housing (p ex-housing). This housing by a permanent pressure with air or inert gas keeps away a potential explosive atmosphere. Depending on the application and existing explosion protection zone, before using the devices or controlsystems the housing must be flushed. This will ensure that a possibly in the housing existing explosible atmosphere will be removed.

                           Permanent pressure!

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System build up of purge systems

Build up of pressurized systems

Modern pressure systems consist of an integrated control unit, with all electronic and pneumatic components such as controller, pressure sensors, flow measuring device, sparking lock outlet, etc.. In addition, input on ex-p-housing an adjustable throttle valve and a magnetic valve for the flushing. Both components can be mounted inside or outside the Ex p housing . There are the operating modes "Through constant flushing," in which the ex-p housing is permant flooded by air or an inert gas , and "compensate for the leakage losses", in which after the the flushing phase the outlet is closed and only so much air or inert gas flows into the housing, that a minimum pressure is maintained. Most applications are based on the "compensate for the leakage losses."

                       Always the safe side

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Compensate of leakage losses and protection types of purge systems 

In this mode, after the completion of a transitional flushing phase a mBar pressure will be maintained within the ex p housing. On the gas entrance digitasl flushing vales and proportional flushing valves can be used for the flushing phase



The overpresirized protection is divided into three protection types, broken down as follows distinguished:


   


    * Typ "px": The zone classification within the housing will decrease from Zone 1 to Non explosive
    * Typ "py": The zone classification within the housing will decrease from Zone 1 to Zone 2
    * Typ "pz": The zone classification within the housing will decrease from Zone 2 to Non explosive.

 

                The right system for your application!