Dynamic elaboration on the Art & Science of Hazardous Area Protection
The most versatile component used in electrical equipment in Hazardous Areas is the ENCLOSURE.
It is THE core product of almost all multinational Hazardous Area Equipment manufacturers.
Analysis of Important Parameters of Hazardous-Area-Safe enclosure
(What follows is not factual about the fabrication process which is employed by today’s industry to make Hazardous-area-safe enclosures )
Nature of the Material of the Enclosure
The material of the enclosure will reveal the nature of the TYPE TESTES , specially the PRESSURE TEST.
It is logical to conclude that the metallic enclosure can withstand the over-pressure of an internal explosion ,as compared to a non-metallic enclosure .
The tests of ability of the enclosure to withstand pressure is stated in details in IEC 60079-1-(Edition 2014) Section 15.2.2 & 15.2.3
(1.5 times the reference pressure – Section 220.127.116.11)
This test marks the boundary between Ex d & Ex e
Another way to understand the concept of INCREASED SAFETY domain . Consider the following graphic presentation of an Ex e Enclosure with components.
In reality the protection protocol is distributed all over the participating components.
Any individual component is surely certified but may carries an Ex Component Certificate .
The Protection Protocol is distributed over all the comprising components (each component carries a separate Ex component certificate ) and the assembly carries an equipment certificate.