top of page

Motors with integrated speed control


Variable speed drive

Speed control of explosion-proof electric motors is a challenge in ATEX environments. Variable motor speed is achieved using a variable speed drive, which has to be installed in a safe zone. Elnor succeeded in integrating a variable speed drive into the explosion-proof motor enclosure.

Integrated speed control reduces the overall purchase cost and avoids having a remote speed control installed in a terminal box or outside the ATEX-zone. In addition, the integration eliminates the risk for motor winding damage due to peak voltage because it minimizes the cable distance between the motor and its motor control.


Speed control in practice

Remote speed control is achieved through a 0-10V voltage signal, a 0-20mA current signal or a turning knob on the motor enclosure. 


Typical speed control applications cover electric motors up to 700 Watt in ATEX applications where mixing, dosing or other speed adjustments offer added value. This is the case in paint mixing machines, for example.



Speed range

  • From 0 to 4000 rpm

Motor power

  • B3, B14 or B5 flange coupling

  • Up to 750W shaft power in S2-60’ duty cycle

  • Up to 550W in S1 duty

Electrical input

  • 1ph 220-240V 50/60Hz

Input signal speed control

  • 4mA – 20mA

  • 0V - 10V

  • Potentiometer (knob control)

Integrated design

  • The electronic card is integrated inside the motor. This results in a very compact and explosion proof design.

ATEX, IECEx and Inmetro approved

  • The complete motor, with the control card included, is approved according: Ex II 2 G Ex d IIB T6 to T3 Gb


Contact Elnor for additional information or a price quotation.

Contact us
bottom of page