Electronic – Why doesn’t the shaft of a running induction motor cause an electric shock

The problem is that the rotor and stator must have spaces called slots, in the iron for the conductors. The conductors and air in the slots have a lower reluctance than the reluctance of the iron. There are more slots than there are poles in the stator. The windings are distributed among the slots to form distributed poles. Their is a different numbers of slots used for the stator and rotor. Those two features prevent the rotor from becoming locked or "cogged" in the minimum reluctance position that would otherwise exist.

Even with proper selection of the number of stator and rotor slots, there can be reluctance variations at different rotor angles that cause torque fluctuations and inflections in the torque vs. speed curve. Skewing the rotor slots mitigates that effect.

Here is a picture of the rotor and stator of a 4-pole, permanent-split capacitor, single-phase induction motor.

• If the windings in the motor were windings of a transformer, you are probably right - but this is a motor and therefore the two windings in serie are wound in opposite directions and may not be considered as additive. The windings don't share the same iron core position either so the magnetic fields from the different field windings are not 'in line' as they are in a transformer. It seems like you are messuring the input voltage + the induced voltage of opposite polarity from the second winding. Looking forward to any comments