ATEX motors

Different kinds of protection can be applied to motors. In the table underneath, you can find the type of protection you need for the different zones of Group II.

Zone 0 and 20 do not appear in the table. Motors cannot be used in those zones.





Group indication

Temperature Indication



II 2 G


1 & 2

IIA, IIB, IIC, indicated seperately

T Class must be indicated



II 2 G

Increased Safety

1 & 2

II suffices (no subdivision A, B or C)

T Class must be indicated

Tripping time tE


II 3 G



II suffices (no subdivision A, B or C)

T Class must be indicated



II 2 D

Dust ignition proof

21 & 22

Not applicable

T (Absolute) must be indicated



II 3 D

Dust ignition proof

22 (only constructive dust)

Not applicable

T (Absolute) must be indicated


Flameproof motors EExd

Those motors are designed to stop a flame from spreading:

  • In an Eexd motor no gaps (flamepaths) can exceed mandatory dimensions. Gases and vapours are sub-divided according to Maximum Experimental Safety Gap (MESG). Different Eexd motors exist depending on which gases of group IIA, IIB or IIC are used.
  • The motor is physically capable of withstanding an internal explosion without transmitting this to the external atmosphere 

Increased safety motors EExe

This increased safety consists of:

  • Protection against axcessive temperatures
  • Protection against sparks and arcs

Both items above apply for:

  • Inner and outer parts of the motor
  • Service, start and in case of a locked rotor (stall)

For this last demand, a specified time tE is defined. This is the tripping time of a special protection device needed for these motors.

Non sparking motors motors EExnA

These motors are designed so that no sparks can occur in normal operation and use within the ratings specified by the manufacturer. Thermal requirements due to starting or accidental stalling are excluded (in contrast to Eexe motors).

Dust-ignition proof motoren (DIP)

Those motors are designed so that:

  • No potentially explosive atmosphere can penetrate inside the motor. Ingress is prevented by the IP protection (IP 55 of IP 65).
  • The maximum surface temperature outside the motor must not exceed the temperature class for which the motor is certified
  • No sparks may occur outside the motor enclosure

Most manufacturers of DIP-motors certify their motors for 125°C; 2 types exist:

II 2D T125°C IP 65

  • Must be used for zone 21
  • Must be used for zone 22 if the dust is conductive
  • May be used for zone 22 if the dust is non-conductive

II 3D T125°C IP 55

  • Must be used for zone 22, only when the dust is non-conductive