ATEX types of protection
A type of protection is the method used to prevent electrical equipment from igniting the explosive atmosphere. Each type has its own standard in the EN/IEC 60079 series.
| Code | Type of protection | Principle | Standard |
|---|---|---|---|
| Ex d | Flameproof enclosure | The enclosure withstands an internal explosion and prevents it from spreading outside | EN/IEC 60079-1 |
| Ex e | Increased safety | Additional measures against excessive temperatures, arcs and sparks | EN/IEC 60079-7 |
| Ex i | Intrinsic safety | The circuit energy is limited below the ignition threshold | EN/IEC 60079-11 |
| Ex t | Protection by enclosure (dusts) | The enclosure prevents dust from entering and limits the surface temperature | EN/IEC 60079-31 |
| Ex p | Pressurisation | A protective gas keeps the enclosure at overpressure | EN/IEC 60079-2 |
| Ex m | Encapsulation | Hazardous parts are embedded in a resin | EN/IEC 60079-18 |
| Ex q | Powder filling | Hazardous parts are embedded in sand or quartz | EN/IEC 60079-5 |
| Ex o | Liquid immersion | Hazardous parts are immersed in a protective liquid | EN/IEC 60079-6 |
Ex d: the flameproof enclosure
The explosion can occur inside, but it stays contained. The flamepaths between cover and body are machined to precise tolerances: hot gases escaping through them are cooled and cannot ignite the outside atmosphere. It is the ideal type for housing equipment that produces sparks: contactors, circuit breakers, relays. Our Ex d enclosures
Ex e: increased safety
The equipment produces no arcs or sparks in normal service, and additional measures (certified terminals, clearance and creepage distances, limited temperatures, IP54 minimum, impact resistance) guarantee it. It suits junction boxes and control stations fitted with certified components. Our Ex e enclosures
Combining types of protection
One assembly often combines several types: an Ex d enclosure for the equipment, connected to an Ex e box, with Ex d push buttons built into an Ex e control station. Our design office chooses the best combination for your application.
Read also: Intrinsic safety Ex i in detail