Hitachi RAC-18WED Service Manual page 54

12. Stepping motor drive circuit
[Connector circuit waveform while the motor runs]
Voltage waveforms of different phases as viewed from
the OV line while the motor rotor is turning counterclockwise
as viewed from the shaft side
4 terminal
3 terminal
2 terminal
1 terminal
・Each stepping motor runs as excited in 1 or 2 phases at 100 PPS or 200 PPS.
・The excitation pattern passes the microcomputer (IC601) and then the driver IC and excites the coil of each stepping motor.
5 ms. or 10 ms.
Fig. 12-2
Fig. 12-1
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