It is possible to measure the motor dimensions to determine the IEC frame reference of a motor.
Measuring from the motor foot to the centre of the motor shaft wil correspond to the motors IEC frame dimension

IEC Frame references are as follows:
| 56 |
| 63 |
| 71 |
| 80 |
| 90 |
| 100 |
| 112 |
| 132 |
| 160 |
| 180 |
| 200 |
| 225 |
| 250 |
| 280 |
| 315 |
| 355 |
| 400 |
AmTecs Ltd
Tealgate, Charnham Park
Hungerford, Berkshire
RG17 0YT, United Kingdom
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