I have this motor and its power supply control board in one. Once it was used in a window air conditioning to power a fan. I can not find any schematics. I hope these pictures give enough information as I am trying to run the motor.

As you might notice on the controller there plug ins for everything. One to the motor (3 wires). One plug (consisting of 5 wires) that goes to the hall of the motor (3 hall and two to power it). In the middle of the board you will notice PWM pin (4 wires), this is the plug that has the black tape on it. I soldered couple of wires that was severed close to the plug. enter image description here You will also notice main AC power supply 220 volts on the board. You can also notice 4 other male connections sticking out next to power-in that seem to be for 4 speed control setting.

I am assuming that the PWM and the 4 male connection were on the user interface that was hooked up for 4 different speed of the motor. The PWM has 4 pins. I assume that with 4 pins, it implies the ground and power for two wires and the third for tach and the 4th PWM. The wire colors on the pwm on this motor is Blue, white, black and brown. I assume Blue to pulse adjust (depending on voltage supply), white is fed power to detect RPM, and the other two black, ground and brown power supply (maybe around 5 volts).

First I thought if I could use Arduino to feed the PWM. However I would think that require program and codes which would be another story.

However I am wondering if I supply power to the PWM (the blue wire), possibly 5 to 10 volts, and not even concern with the tach white wire, supply 5 volts to the brown wire, would that be a safe bet? I still need to consider those 4 motor RPM connection and relate them to PWM for speed.

You will also notice in the first picture that has the heat sink visible, right below the heat sink you can see a switch. You can see the word "ON". That little deal has two switch, where you click to place each gives total of 4 different speed on the motor. There respective positions for 4 different speeds is described by the 4 male plugs and pwm hook up right there on the board floor.

I am wondering if anybody have a take on what I am doing. Just exploring how things work. Thank you so much in advance.

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    \$\begingroup\$ Welcome to EE.SE! ”I am assuming” ”would that be a safe bet” In engineering, you don’t assume nor bet, you start by measuring. Use your oscilloscope and check if your assumed PWM theory is correct. \$\endgroup\$
    – winny
    Commented Apr 3, 2020 at 7:27
  • \$\begingroup\$ Certainly no one is assuming that I have an oscilloscope and furthermore if I had one, I would know what it is that I should and would check. And for someone like myself without a formal education plus English being my second language I am fish out of water. In the meantime certainly no one is obligated to burden themselves with answering my question or inquires. My apologies. \$\endgroup\$ Commented Apr 4, 2020 at 8:37
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    \$\begingroup\$ It is assumed you have access to an oscilloscope. You seem to have taken objection to having your post corrected for language. This does not bode well for getting any help. \$\endgroup\$
    – winny
    Commented Apr 4, 2020 at 9:48
  • \$\begingroup\$ I ask you not to harass me please. I will be saying nothing more to you. Thank you. \$\endgroup\$ Commented Apr 5, 2020 at 16:13


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