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Entry type: FAQ Entry ID: 38616098, Entry date: 04/04/2016

MICROMASTER 4 (MM4): Substitute Fan for frame size F (FSF)

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When comparing spare part fan and original assembled fan for a MM4 frame size F, you might detect differences in size in some cases.

The ordered substitute Fan for MM4 FSF, does not match! What can I do?

The spare part fan is larger than the original assembled fan.

  • This is caused by the different power ratings of the frame size F units. They vary between 30, 37, 45, 55 and 75 kW.
  • To save costs we have only one spare part fan for all power ratings.
  • The biggest fan is chosen as spare part for all frame size F units.
  • To allow assembling of bigger fans at lower power ratings, the frame size F housings have extra drillings where needed.


Order Number (MLFB) of MM440 FSF: 6SE6440-2UD35-5FA1

Order Number (MLFB) of spare fan: 6SE6400-7AA00-0AB0

The three drillings on the larger radius (90 mm) are for assembling a spare part fan.

The three drillings on the smaller radius (81 mm) are for assembling an original fan (only at the factory).

The Replacement Instructions MM430/MM440 Frame Size F Fan please find at: 109743082 


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