Sync Speed
If a 2 pole AC motor has a synchronous speed of 3,600 rpm, what is its line voltage frequency in Hz?
Expand Hint
Synchronous speed is the speed of the magnetic field rotation produced by an induction motor’s stator (stationary part of a rotary system), which is always constant once the hardware is designed (assuming you don’t go to another country with a different electrical supply frequency standard).
Hint 2
The synchronous speed for an AC motor is:
$$$n_s=\frac{(60)f}{(p/2)}$$$
where
$$f$$
is the line voltage frequency, and
$$p$$
is the number of magnetic poles.
Synchronous speed is the speed of the magnetic field rotation produced by an induction motor’s stator (stationary part of a rotary system), which is always constant once the hardware is designed (assuming you don’t go to another country with a different electrical supply frequency standard). The synchronous speed for an AC motor is:
$$$n_s=\frac{(60)f}{(p/2)}$$$
where
$$f$$
is the line voltage frequency, and
$$p$$
is the number of magnetic poles. Note in the equation, multiplying the frequency by 60 converts hertz to rotations per minute (rpm). Thus,
$$$3,600rpm=\frac{(60)f}{(2/2)}$$$
$$$f=\frac{3,600(1)}{60}=60\:Hz$$$
60 Hz
Time Analysis
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