I'm trying to hardwire a fan motor to always run on max. Currently, it has a circuit board that allows you to adjust the speeds and requires a bit of fiddling to turn on and set the speed when the fan is plugged in. The fan has 4 speeds and defaults to 2 when turned on. I would like the fan to run at max(4) as soon as it's plugged in.
I'm unfortunately unable to access the motor as the screws that secure the motor to the fan housing are blocked by the fan fins and the fins a somehow (I'm guessing glued) very strongly attached the to the motor shaft. The fan is the Geek Aire Digital Air Circulator AF1S1.
The motor has 5 wires: Blue, Black, Red, White, Yellow
I measured the AC voltage between blue and each of the other colors at each of the fan speeds:
| Speed | Black | Red | White | Yellow |
|---|---|---|---|---|
| 1 | 110V | 45V | 35V | 27V |
| 2 | 140V | 55V | 45V | 31V |
| 3 | 160V | 60V | 50V | 35V |
| 4 | 170V | 64V | 54V | 38V |
On the circuit board, the it looks like black is connected to AC hot and blue is connected to AC neutral while red, white, and yellow are connected to 3 triacs. Red and white are each connected to a BT138 triac while yellow is connected to a JST134K-600D triac.
I marked where each color wire connected to on the pictures of the circuit board below. The unmarked connections went to 2 other motors are oscillate the fan(not relevant to this problem). The 6 black modules across the middle are L2236 MOC3021 optoisolator triacs.
I also measured the resistance between each of the wires (all in ohms):
| white | blue | red | yellow | |
|---|---|---|---|---|
| black | 17.5 | 44.7 | 12.5 | 24.8 |
| blue | 27.4 | 32.5 | 20 | |
| yellow | 7.5 | 12.8 | ||
| white | 5.2 |
I'm honestly very lost on how the triacs and optoisolators work so any help would be greatly appreciated.
