274
IEC/NEMA Comparison
Dimensions in Millimeters
kW/Hp** Frame Assignments
IEC
H
A
B
K
D
C
E
3 Phase – TEFC
NEMA D
2E
2F
H
U BA N-W 2 Pole
4 Pole 6 Pole
56
56
90
71
5.8
9
36
20
— — —
NA — — — — — — — — — —
63
63
100
80
7
11
40
23 .25 kW .18 kW —
42 66.7 88.9 42.9 7.1
9.5 52.4 28.6 1/3 Hp 1/4 Hp
71
71
112
90
7
14
45
30
.55
.37
48 76.2
108 69.9 8.7
12.7 63.5 38.1
3/4
1/2
80
80
125
100
10
19
50
40
1.1
.75
.55 kW
56 88.9 123.8 76.2 8.7
15.9 69.9 47.8 1 1/2
1
3/4 Hp
90S
90
140
100
10
24
56
50
1.5
1.1
.75
143T 88.9 139.7 101.6 8.7
22.2 57.2 57.2
2
1 1/2
1
90L
90
140
125
10
24
56
50
2.2
1.5
1.1
145T 88.9 139.7 127
8.7
22.2 57.2 57.2
3
2
1 1/2
100L
100
160
140
12
28
63
60
3
2.2
1.5
NA — — — — — — — 4
3
2
112S
112
190
114
12
28
70
60
3.7
2.2
1.5
182T 114.3 190.5 114.3 10.4 28.6 69.9 69.9
5
3
2
112M
112
190
140
12
28
70
60
3.7
4
2.2
184T 114.3 190.5 139.7 10.4 28.6 69.9 69.9
5
5.4/5
132S
132
216
140
12
38
89
80
7.5
5.5
3
213T 133.4 215.9 139.7 10.4 34.9 88.9 85.9
10
7 1/2
132M
132
216
178
12
38
89
80
— 7.5
5.5
215T 133.4 215.9 177.8 10.4 34.9 88.9 85.9
— 10
7 1/2
160M*
160
254
210
15
42
108 110
15
11
7.5
254T 158.8 254 209.6 13.5 41.3 108 101.6
20
15
10
160L*
160
254
254
15
42
108 110
18.5
15
11
256T 158.8 254
254 13.5 41.3 108 101.6
25
20
15
180M*
180
279
241
15
48
121 110
22
18.5
284T 177.8 279.4 241.3 13.5 47.6 120.7 117.4
— 25
180L*
180
279
241
15
48
121 110
22
22
15
286T 177.8 279.4 279.4 13.5 47.6 120.7 117.4
30
30
20
200M*
200
318
267
19
55
133 110
30
30
324T 203.3 317.5 266.7 16.7
54 133.4 133.4
40
40
200L*
200
318
305
19
55
133 110
37
37
22
326T 203.2 317.5 304.8 16.7
54 133.4 133.4
50
50
30
225S*
225
356
286
19
60
149 140
— 37
30
364T 228.6 355.6 285.8 16.7 60.3 149.4 149.4
— 50/
75
40
225M*
225
356
311
19
60
149 140
45
45
37
365T 228.6 355.6 311.2 16.7 60.3 149.4 149.4 60/
75
60/
75
50
250M*
250
406
349
24
65
168 140
55
55
405T 254 406.4 349.3 20.6
73 168.4 184.2 75/
100
75/
100
280S*
280
457
368
24
75
190 140
— — 45
444T 279.4 457.2 368.3 20.6 85.7 190.5 215.9
— — 60/
100
280M*
280
457
419
24
75
190 140
— — 55
445T 279.4 457.2 419.1 20.6 85.7 190.5 215.9
— — 75/
125
* Shaft dimensions of these IEC frames may vary between manufacturers.
** Horsepower listed is closest comparable rating with similar mounting dimensions. In some instances this results in
greater Hp rating than required. For example, 37 kW, 4 pole converts to 50 Hp but nearest Hp rating in the NEMA frame
having comparable dimensions is 75 Hp. In these instances the Hp rating printed in black is the direct conversion, and Hp
printed in
Red
is the Hp of the dimensionally desirable frame.
OBSERVE CAUTION if the drive train or driven
load is likely to be damaged by the greater Hp
.
Equivalent Hp can be calculated by multiplying the kW rating by 1.341. Multiply Hp by .7457 to convert Hp to kW.
To convert from millimeters to inches, multiply by .03937. To convert from inches to millimeters, multiply by 25.40.
Fraction/Decimal/Millimeter Conversions
Fraction
Decimal
Millimeter
Fraction Decimal
Millimeter
MM
Inch
1
64
.015625
0.397
33
64
.515625
13.097
1
.0394
1
32
.03125
0.794
17
32
.53125
13.494
2
.0787
3
64
.046875
1.191
35
64
.546875
13.891
3
.1181
1
16
.0625
1.588
9
16
.5625
14.288
4
.1575
5
64
.078125
1.984
37
64
.578125
14.684
5
.1969
3
32
.09375
2.381
19
32
.59375
15.081
6
.2362
7
64
.109375
2.778
39
64
.609375
15.478
7
.2756
1
8
.125
3.175
5
8
.625
15.875
8
.3150
9
64
.140625
3.572
41
64
.640625
16.272
9
.3543
5
32
.15625
3.969
21
32
.65625
16.669
10
.3937
11
64
.171875
4.366
43
64
.671875
17.066
11
.4331
3
16
.1875
4.763
11
16
.6875
17.463
12
.4724
13
64
.203125
5.159
45
64
.703125
17.859
13
.5118
7
32
.21875
5.556
23
32
.71875
18.256
14
.5512
15
64
.234375
5.953
47
64
.734375
18.653
15
.5906
1
4
.25
6.350
3
4
.75
19.050
16
.6299
17
64
.265625
6.747
49
64
.765625
19.447
17
.6693
9
32
.28125
7.144
25
32
.78125
19.844
18
.7087
19
64
.296875
7.541
51
64
.796875
20.241
19
.7480
5
16
.3125
7.938
13
16
.8125
20.638
20
.7874
21
64
.328125
8.334
53
64
.828125
21.034
21
.8268
11
32
.34375
8.731
27
32
.84375
21.431
22
.8661
23
64
.359375
9.128
55
64
.859375
21.828
23
.9055
3
8
.375
9.525
7
8
.875
22.225
24
.9449
25
64
.390625
9.922
57
64
.890625
22.622
25
.9843
13
32
.40625
10.319
29
32
.90625
23.019
27
64
.421875
10.716
59
64
.921875
23.416
7
16
.4375
11.113
15
16
.9375
23.813
29
64
.453125
11.509
61
64
.953125
24.209
15
32
.46875
11.906
31
32
.96875
24.606
31
64
.484375
12.303
63
64
.984375
24.003
1
2
.5
12.700
1
1.0
25.400
To convert millimeters
into inches, multiply
by .03937.
To convert inches into
millimeters, multiply
by 25.40.
3600 RPM
1800 RPM
1200 RPM
900 RPM
NEMA Frame Assignments
Open and TEFC (TEFC Frame in Green where different than open)
“T”
Frames
1964
“U”
Frames
1952
Original
NEMA
Frames
NEMA
Frame
Program
“T”
Frames
1964
“U”
Frames
1952
Original
NEMA
Frames
“T”
Frames
1964
“U”
Frames
1952
Original
NEMA
Frames
“T”
Frames
1964
“U”
Frames
1952
Original
NEMA
Frames
1
143T
182
203
145T
184
204
182T
213
225
1 1/2
143T
182
203
145T
184
204
182T
184
224
184T
213
254
2
145T
184
204
145T
184
224
184T
213
225
213T
215
254
3 145T /
182T
184
224
182T
213
225
213T
215
254
215T
254U 284
5 182T /
184T
213
225
184T
215
254
215T
254U
284
254T
256U 324
7 1/2 184T /
213T
215
254
213T
254U
284
254T
256U
324
256T
284U 326
10 213T /
215T
254U
284
215T
256U
324
256T
284U
326
284T
286U 364
15 215T /
254T
256U
324
254T
284U
326
284T
324U
364
286T
326U 365
20 254T /
256T
284U/
286U
326
256T
286U
364
286T
326U
365
324T
364U 404
25 256T /
284TS
286U/
324U
364S/
365S
284T
324U
364/
365
324T
364U
404
326T
365U 405
30 284TS /
286TS
324S/
326S
364S/
404S
286T
326U
365/
404
326T
365U
405
364T
404U 444
40 286TS /
324TS
326S/
364US
365S/
405S
324T
364U
404/
405
364T
404U
444
365T
405U 445
50 324TS /
326TS
364US
404S/
444S
326T
365US
405S/
444S
365T
405U
445
404T
444U 504U
60 326TS /
364TS
365US/
405US
405S/
445S
364TS
404US/
405US
444S/
445S
404T
444U
504U
405T
445U 505
75 364TS /
365TS
404US/
444US
444S/
504S
365TS
405US/
444US
445S/
504S
405T
445U
505
444T
— —
100 365TS /
405TS
405US/
445US
445S/
505S
404TS/
405TS
444US/
445US
504S/
505S
444T
— — 445T
— —
125 404TS /
444TS
444US
504S
405T /
444TS
445US
505S
445T
— —
— — —
150 405TS /
445TS
445US
505S 444TS/
445TS
— — —
— — —
200
444TS
445TS
— — —
— — —
250
445TS
— — —
— — —
1...,266,267,268,269,270,271,272,273,274,275 277,278,279,280,281,282,283,284,285,286,...324