Gearbox inputs are made to IEC motor dimensions, so the match is read from the motor's frame number and flange type. For example, the HEM63 worm gearbox page lists B5 and B14 inputs for frames 71, 80 and 90; a frame 80 motor needs a gearbox with an 80 B5 or 80 B14 input.

Checklist:

  • Frame number: the IEC size on the motor nameplate (e.g. 90L → 90).
  • Flange type: on a B5 flange the fixing holes are clearance holes and the flange diameter is large; a B14 flange is smaller and has tapped holes on its face.
  • Shaft: diameter, length and key; the motor shaft must seat in the gearbox input bore without play.
  • Fixing: a motor flanged to a gearbox is usually chosen without feet; fixing it by both flange and feet can cause strain with small misalignments.

For flanged motor options see the B5 and B14 flange-mounted electric motors page. Flange and shaft dimensions are confirmed when ordering.