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1.2 Motor drive force
1.2.1 Motor and frequency
Motor speed is changed by varying the frequency of current owing through motors.
Frequency is discussed in more detail in this section.
◎
Frequency
Outlets in homes, for example, supply power at 100V/50Hz and 200V/60Hz specications.
"V" represents voltage and "Hz" represents the frequency.
Frequency values are usually shown in a graph like this. For example, frequency 60Hz means that there are 60
waves between positive and negative per second.
60Hz
1 sec
60 cycles
V
t
V
t
120Hz
1 sec
120 cycles