Explosionproof switchgear assemblies in the type of protection ‘nR’
(Equipment without built-in components thatgive off arcs or sparks during normal operation)
The explosionproof switchgear assemblies are intended for use in Zone 2 explosive gas atmospheres according to IEC/EN 60079-0 and IEC/EN 60079-15. IEC/EN 60079-15 ‘Equipment protection by the type of protection‘ covers explosionproof equipment for the equipment protection level ‘Gc’ (Zone 2). The range of polyester enclosures has 4 compatible dimensions, each with enclosure covers in 2 different heights
Before dispatch, each enclosure is subjected to a halftime pressure test. The test is carried out to determine the time to change to half the initial pressure value from 3 to 1.5 mbar. This shall not be less than 180 seconds. Testing of enclosures after installation is not required. For this reason, the enclosures do not feature a test port.
The restricted breathing polyester enclosures are subjected to ageing tests (thermal endurance to heat and cold, impact test followed by IP test). The test for leakage in accordance with IEC/EN 60079-15 is not carried out until after the IP test. The halftime value of the polyester enclosures is substantially higher than the requirements of the standard.
Non-explosionproof electronic components such as access points, WLAN antennas and GSM modules can be installed in the restricted breathing enclosures.
In accordance with IEC/EN 60079-17 ‘Electrical installations inspection and maintenance’, restricted breathing enclosures without built-in components that give off arcs and sparks during normal operation shall be subjected to periodic close inspections to ensure that the enclosuresand cable glands are not damaged