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IEC Frame Size

General

The IEC 72 defines motor frame size standards for regions that use SI units.

Regions using "inch" units work with NEMA standards (see page NEMA Frame Size). Therefore most motor series are offered with both standard frame sizes.

Usual IEC sizes

All dimensions in mm

Figure: Reference graphic for dimensions

IEC Torque*
in Nm
 Flange
(P)
Bolt Circle
(M)
Mounting Holes
(S)
Register Diameter
(N)
Shaft Diameter
(D)
Shaft Length
(E)
Keyway
width (F)
remaining shaft
thickness
to keyway (G)
63 1,22 140 115 9 95 11 23 4 8,5
71 2,8 160 130 10 110 14 30 5 11
80 8,25 200 165 12 130 19 40 6 15,5
90 18,5 200 165 12 130 24 50 8 20
100 31,5 250 215 14 180 28 60 8 24
112 31,5 250 215 14 180 28 60 8 24
132 92,5 300 265 14 230 38 80 10 33
160 132 350 300 19 250 42 110 12 37
180 212 350 300 19 250 48 110 14 42.5
200 345 400 350 19 300 55 110 16 49

 * Rated torque with permanent operation according to IEC 72

Mechanical tolerance

ISO tolerance to DIN 748, DIN 7160, DIN 42948 .

Diameter shaft end (dimension „D“)

up to 28 mm

j 6

38 to 50 mm

k 6

more than 50 mm

m 6

Register Diameter (dimension „N”)

up to 230 mm

j 6

more than 230 mm

h 6

Recommended shaft basis fit

Hub alignment Hole basis fit Shaft basis fit
on long shafts, fixed H7/j6 J7/h6, h8, h9
on shaft end, fixed H7/k6, m6 K7, M7/h6, N7/h8
on shaft, slidable H7/h6, j6 H7, J7/h6, h8

Recommended tolerance fields for key width

Hub character Key width Fit character
Shaft Hub
slideable H9 D10 Sliding fit
easily mountable N9 JS9 Transition fit
for bi-directional torque P9 P9 Tight fit