Technical data

MKE UL/CSA Potentially-explosive areas 4-3
DOK-MOTOR*-MKE*UL/CSA*-PR01-EN-P
Ignition protection classes, groups and temperature classes
Electrical equipment for potentially explosive areas is classified into:
The manufacture of electrical equipment is designed according to the
ignition protection class. The requirements are specified in special
standards.
Ignition protection class Designation Standard
Oil immersion o EN 50015: 1998
Excess pressure immersion p EN 50016: 1995
Sand immersion q EN 50017: 1998
Compression-proof
encapsulation
d EN 50018: 1994
Increased safety e EN 50019: 1994
Intrinsic safety, category a ia EN 50020: 1994
Intrinsic safety, category b ib EN 50020: 1994
Encapsulation m EN 50028: 1987
Fig. 4-1: Ignition protection classes
Electrical equipment of these ignition protection classes is certified by a
neutral party after an inspection of the design.
· Group I: Electrical equipment for firedamp-endangered excavations.
· Group II: Electrical equipment for all potentially explosive areas, other
than firedamp-endangered excavations.
The electrical equipment of Group II is subdivided according to the
characteristics of the potentially explosive atmosphere for which they are
specified.
For ignition protection classes "d" (compression-proof encapsulation) and
"i" (intrinsic safety), electrical equipment of Group II is subdivided into IIA,
IIB and IIC (see Appendix A of EN 50014 :1992).
For all ignition protection classes, electrical equipment of Group II must
be identified according to Fig. 4-2, depending on its maximum surface
temperature.
Ignition protection classes
Groups