TFL (No. 1): PWM channel with the lowest te mperature setting, when ON, the lowest PWM of FAN1 is 40%; when OFF, the minimum PWM of FAN1 is 20%. Stall Alarm Minimum Speed: 700-800 rpm. BF1, BF2 (No.4,5) correspond to FAN1, FAN2 stop alarm function switch.
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