Slip s = (Ns − N) / Ns - the fractional difference between synchronous and rotor speed. Directly proportional to rotor losses and torque.
Formula
$$ s = \frac{N_s - N}{N_s} $$
Symbol legend
| Symbol | Meaning | Unit | Source |
|---|---|---|---|
| $N_s$ | Synchronous speed | rpm | grid × pole ratio |
| $N$ | Rotor speed (shaft) | rpm | tachometer |
| $s$ | Slip | - | result |
Sources
- IEC 60034-12 - Starting performance of rotating motors.