85
5-13. Fan Motor (BLDC) Drive Circuit
5. Circuit Descriptions
Voltage of motor Remark
Measure b
(F-FAN)
Measure C
(R-FAN)
Measure d
(C-FAN)
In the normal operation, MICOM
No. 40, 41 and 42 applies a
constant frequency; and
MICOM defects the signal to
check the failure of motor.
(frequency(Hz)×12 = motor rpm)
High 11.1V 10V 10V
Low 10V 10V 8.3V
Under the conditions, the fans will be operated in 2 options, such as High
and Low mode. Generally, it is operated in the High mode during a day time
and in the Low mode at night.
Note
1-3) When the motor rpm is in 600∼700, it will stop automatically and it tries to
resume after 10 seconds. If the motor is not working properly after 5 time trials,
it will rest for 10 minutes, then try to resume again. This process will be done
continuously.