DC Fan this function is to use external adjustable resistance to control the speed, this adjustable resistor, can be 10K to the maximum of 100K between any resistance, the fan speed will be proportional to the resistance of the adjustable resistor changes linearly, and when the resistance of the adjustable resistor reaches the maximum value, the fan reaches the maximum speed, the fan after the customer chooses the RPWM function will have the CS-constant speed function, IR-impulse current protection, CL (current limiting) function, in addition, Rpwm will follow the additional identification bar code, for example: R 2510025100B 400: "R" means the input signal is RPWM. The first "25,100" represents the resistance of the two most representative adjustable potentiometers (25% of the total resistance, 100% of the total resistance) . The second "25,100" represents the two most significant RPM's (25% of full speed and 100% of full speed) . To sum up, "2510025100" means: first, assuming the total resistance of the adjustable potentiometer is 100K, then when the resistance value of the adjustable potentiometer is manually adjusted to 25K, the speed of the DC fan is 1000RPM (25% of the full speed) , when the resistance value of the adjustable resistor is manually adjusted to 100K, the fan speed is 4000RPM (100% of full speed) . "B" indicates that RPWM curve mode is B mode (Fig. 5b-b) . The special feature of Mode B is that when the resistance of the adjustable potentiometer is manually adjusted to less than 25K, the DC fan will stop working. The last number encoded, "400" , is the maximum speed of the fan divided by 10, from which the maximum speed of the Fan (400 * 104000 rpm) can be calculated.

 This is the function of RPWM on DC fan introduced by Dong Xing Yue. We can customize it according to customer's special requirement. If you want to know more about DC fan, you can click on:http://www.dxymotors.com