The controller automatically adapts to dual voltage, i.e. DC 12V and 24V power input systems. The maximum input voltage is 17V for DC 12V systems and 31.5V for 24V systems. A 12V DC fan can be connected between the terminals (F+) and (F-) of the controller, the positive terminal of the fan is connected to the (F+) terminal of the controller and the negative terminal is connected to the (F-) terminal of the controller. The output between terminals (F+) and (F-) will always remain at 12V when the input voltage to the controller exceeds 12V. The fan must be a 12V DC fan regardless of whether the input voltage system is 12V or 24V.
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