Universal fan control module teardown - with schematic
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- เผยแพร่เมื่อ 12 ก.ย. 2024
- A look at a generic Chinese controller for repairing air conditioner units (not the compressor type).
This universal module can control three-speed fans, and two extra loads like a swivel motor and pump for an evaporative cooler.
It's functionally very similar to the PCB in a Hepa air filter unit I have here, although much simpler.
It's very minimalist. I think I'd rather it used a small buck regulator for the 5V rail, since the voltage falls significantly when driving three triacs and several LEDs on the display.
The capacitor in series with the coil based sounder is rated 820nF.
If you enjoy these videos you can help support the channel with a dollar for coffee, cookies and random gadgets for disassembly at:- www.bigclive.c...
This also keeps the channel independent of TH-cam's algorithm quirks, allowing it to be a bit more dangerous and naughty.
#ElectronicsCreators
Lol that "stroke" translation really had me. Just in case you're wondering if switching to the medium setting will cause a stroke, in Chinese "stroke" and "medium wind (literal)" writes out the same, although they are pronounced differently (the tones are different for the first character).
As for the mode button: in China a lot of fans have a mode called "natural wind", which aims to simulate, as the name implies, natural wind. But they do a terrible job at it by basically cycling through different speeds. I don't know if it's a thing in other countries, but some Chinese people believe (or are made to believe) that such wind pattern is better than a constant-speed airflow.
Like the poor orientals in 🇰🇷, who believe in/have a phobia of “fan death” = if a fan is left on and blowing on them and they fall asleep they will die, and the fan “must have the “compulsory sleep/safety timer” for them to set if they feel tired
@@samuelfellows6923 I understand some people can be under-educated or ignorant even in S.Korea, but the government buckling to their pressure is what blows my mind.
@@jwhite5008 If it blows your mind, the Koreans are on to something, no single household fan should have sufficient power to blow on your mind while it's still encased in your skull😉.
I have seen an air cooler with that feature it just annoying when the air speed changing with the ramping motor noise
@@darwisyaiman1865 Yes, I find it especially annoying when trying to fall asleep. The ramping noise can be very distracting and it'll keep me awake.
Note the reason why the TRIACs are commoned to +5V is to avoid quadrant 4, (MT2-, G+), which is the least sensitive and would require more gate current to fire. This circuit only triggers the TRIAC in quadrants 2 (MT2+, G-) and 3 (MT2-, G-).
mode varies the speed to create a more 'natural' breeze, my fan does that and it is surprisingly good, seems better than when on a constant speed.
I found that setting very annoying as the white noise is not constant
It is very surprising that this board does not have this feature because it does not require additional hardware all it does is the microcontroller generates a random number and it steps the speed up and down automatically all my electronic controlled fan have it
I have a handheld 'personal' fan that has that feature. Nice to sometimes get rid of the constant 'drone' of a single speed.
@@25566
Me too. The ones I've tried that feature on all also made a horrible vibrating noise fairly often as it cycled the speed up and down. I always felt like this was probably going to do damage over time.
@@lifeai1889It does have that function, see 14:25. ;)
14:53 I have a Japanese fan that does that - it has a setting called “random” that effectively cycles randomly between the four speed settings (and off) at random time intervals to “simulate a natural breeze”. I guess that that’s what at least one of the things the “mode” button on your unit does.
I have a fancy japanese fan too, and i was thinking the same. It's supposed to simulate nature (because the wind outside isn't constant).
Someone I knew showed me the schematic that came with his washing machine. It included timing and switch positions for the motors, the pumps and the valves for each cycle type of the washer. Precisely what you'd need if you wanted to replace the logic in the machine with something like a microcontroller or remote control. The schematics were tucked into a little pocket inside the back of the thing.
In principle I've understood how button and LED multiplexing works, however... In practice I've never really fully understood the process. That diagram and explanation really summed it up for me and made it very clear how it works. Thank you!
Just avoid googling charlieplexing if you value your sanity then...
I have a "tower" (upright) fan which mimics EXACTLY the functions of this module to a "T"; the "mode" setting is for "natural breeze" as it switches through the different speeds to mimic a natural breeze of some sort (mine was made by Lasko/Holmes and was purchased from Walmart)
I do find it fun to trawl through all the random gear to find this type of universal controller. It keeps the imagination going for the possibilities. Thanks Clive.
Universal controllers. That is brillant, I wish we had more of that and modularity and less monolithic products.
Awesome find. Here in Australia remote control fans are no longer available. A few years ago most fans were remote but not now. This module has the potential to be a simple inline unit for non remote fans.
Thats because 99% of fans in Australia are switched on late November and not switched off until about March. By then the remote is long gone.
As a Sparks here in Australia I finding plenty of ceiling Fans with remotes, on the shelves in most fan and light shops
@@Ivorbiggin Sorry, i was referring to pedestal fans.
@@darkman19693 ah right, those POS fans i hate seeing those ones. There shite mostly sold in Bunnings
1:00 I used to have an infrared detector I got from radio shack I have no idea what happened to it I've been looking to buy one off of eBay for years and I can't find anything that I want I'm watching this video and you show me that you can see it through the camera this is ingenious I don't have to spend any money I can just use my phone I was able to fix a remote I thought was bad but it was just the battery It goes to a DVD player Thank you so much for this if You are ever in a live stream I'm going to send you money because of this I really appreciate it
Motors do have short circuit protection, the CCA wire will blow up and disconnect at around double the current.....
That type of module should be available through Big Clive Industrial Corporation. Change the writing to Welsh, or Norse, for more confusion in the instructions. Thank you, keep working.
A smooth & confident Ballet of knowledge, wisdom and danger.
Goes well with a cup of coffee on a cold monday morning.
Thanks Big Man.
Good evening Clive, I am listening to you through my newly acquired SQN-4S location mixer.
The cooling output is for opening a solenoid that lets chilled water into a coil that the fan is blowing air over.
This is very common in office buildings and hotels. Each room would have such a water fan coil.
Usually the water is pumped to an outdoor unit that cools and/or heats it like Daikin EWYQ. In some installations with geothermal they pump the same brine that goes into the heatpump for heating in winter to the coils in summer for cooling.
"Misting fan" is the term your are looking for.
@j.f.christ8421 I am talking about a system with a closed loop water system. The cold water goes through a copper coil in the fan where it heats up. Then the hot water is returned to a central location where it's cooled down again. Just like an air conditioner but with water instead of refrigerant. It is also possible to use water from a lake or well which is discarded after it is heated.
A "misting fan" is an evaporative cooler or "swamp cooler". It only works in very dry climates.
This control device would work equally well for both system.
Yes, and we're wondering why you are rambling on about it
Do you really think this board is for more than just spraying a bit of water in front of the fan blades?
Once again, you could have written "misting fan" instead all that dribble and the world would be a better place.
I am a forester and I have absolutley no clue what you are talking about, but i love it!
Thanks for the explanation on how button multiplexing works. You've mentioned it in other videos but I didn't understand it until now.
That LED button thing is pretty cool. It allows the uC to multiplex the LED user 'experience' and also read the buttons kinda simultaneously. The uC will set whatever logic it wants to for the user on the inputs of the 330R lines, then it turns on the pink circuit, and also reads the input from the 2.2K signal line. Each time it goes through the loop, it is setting user output information and also reading user input information. Seems a pretty efficient 'multi scanner' circuit.
This has potential to be used as a nice home assistant fan controller with a cheap esp. Time to grab one and try it
I'm not sure the triac can trigger at 3.3v
And the esp would need more power
And it will be live at mains voltage
I recommend getting a DC fan which you can directly connect a esp gpio to and control it with pwm which is what I have done
@@lifeai1889@lifeai1889 Don't overthink things.
Cut a track on the board and use a USB power supply for the 5v. (Worry about the mains going back into the USB some other time.)
Add a 3.3v LDO regulator for the ESP.
Add level shifters to keep logic levels happy between the two boards.
Write a bit of code and you're all done! Easy peasy!
Or just buy one premade. Tuya make them already in various forms.
@@j.f.christ8421 maybe its this easy
ive never used triac before
all my appliances run on 12v now and all controled by esphome
I bought severaal of these to add it to ceiling fans that are not remote controlled. I wired the switch to the fan to be always on, and put a blank plate on where the wall switch was. I mounted the remote holder onto it (mine came with a remote controller holder). It works perfectly.
I like the fact that you can use one of these to repair a swamp cooler controller.
Could be fun to see what else you can do with these things...what kind of mischief could you get in to :)
Swamp coolers are AMAZINGLY effective in southern calif and other dry areas, it shocked me when i moved there. The humid air felt ICY...! (being from coastal UK and having moved from midwestern USA, this is not normal LOL)
I never did understand the point of swamp coolers. What's wrong with letting the swamp be as warm as the surrounding dry land?
I used a six channel remote unit to replace my caravan motor mover controller. Cost about six quid, where the original would be over one hundred for a replacement circuit board, worked perfectly.
I have a fan, that recently decided it was going to start changing functions without a button press. Thanks to this channel, I was confident in ripping out the speaker that beeped every time it changed (it was literally every few seconds) i then also completely disconnected the wires from the circut board to the tilt motor. It now no longer moves automatically, but it functions as a fan on low, medium and high as it should. (And every few seconds thinks it's tilt is being turned on by an unknown source. Still no idea why)
Clive, have you considered using an isolation transformer for your workbench? Makes probing around in circuits at live mains voltage a little saver. Keep up the good work, very much enjoying your videos!
I have a type A RCD on my bench and an isolated working area.
@@bigclivedotcomThat's not enough...
In this case your body current must be sufficient to trip the RCD..don't know it's sensitivity level or response time to trip... before saving you.😮
I think Clive enjoys the odd bit of body current to keep him on his toes?
Please bear in mind, an isolation transformer will save you from a Live to earth shock, but it won't save you from a live to neutral shock on the secondary of the transformer.
@@kenaston4220 Yes, you are absolutely right. But even a RCD won't save you in that specific case. Always be careful when playing with live mains voltages. But Clive seems to be doing alright.
Great video, Clive. That controller could also be used to give remote control capability and speed control to ceiling fans and even extractor fans as some of those are three speed.
That is a cute little Chinese device. I needs to come with a small fire extinguisher before I’d want to use it.
I am super interested in that universal washing machine controller. Hopefully you can get your hands on one soon!
With that universal fan controller, you should be able to make all your fans hit that like and subscribe button! :P
I learned what happened in electronics class when you miswire a multispeed fan motor. someone brought a fan in with a broken switch and rigged up another, but got the connections wrong. he turned it on and the fan started up and ran fine. then about 10 seconds later big gouts of smoke came out of the front of the fan and smoked out the whole room.
Cheers for another great video Clive 👍
Am thinking about getting some new boards from manufacturers in the UK and USA for a bit of different reverse engineering videos if you'd like?
Have a great day everyone
I occasionally do proper equipment, but prefer the exciting cost optimised Chinese stuff.
The comment "this is the LUXURY version with big triacs" cracked me up.
I read this as "Universal Fat Controller" but was keen to watch it anyway 😂
I've been looking for something like this to control a large fan in my shed to blow air over my motorcycle if the RH gets near to the dewpoint. I've already written and tested arduino code for a DHT11 temp/humidity sensor. The bike occasionally gets dripping wet under certain conditions (if there's a rapid temperature change from near freezing) and despite being covered in all manner of corrosion inhibitors I still worry about my beloved bike under these conditions.
7:15 which has that peeper connected "slightly halting" whatever, and goes on. Pure comedy gold my man, I love all your videos!
Mode on my cooler is labled "Nature" and is meant to simulate a breeze(according to the manual) I have never used it. XD
It has the same remote as the one in the picture not the ine you actually have
I do enjoy it when BigClive makes me clench my hoop of an evening. Live probing never fails to be exciting. 😅
mode is like having wind in house, goes up and down randomly on our devices.
Over here (at least in Cali which is the only place I've seen them), the ones using water vs compressor are called "swamp coolers"...
The fan control IC is likely to be SC8206 or a derivative.
Thank you. Reading the IC datasheet answered all my questions :)
I saw a video on here with that washing machine controller and I was dubious at first but then after seeing the sheer amount of tearing down the machine, re-fitting wiring, chuffing about with the thing it was at that point I would have said, sod it and just bought a new machine and scavenged all the parts for spares from the old one.
Was it the one where they used random flex for everything, including the earth/ground for live connections.
Interesting product and useful as well, if it lasts
It was also good to see you learning something while doing the video…not sure why you would want to hunt the fan speed up and down like that other than to wind someone up 😁
I've got an ventilator that has a 'mode' position to, this is to creat a socalled 'natural breeze! The ventilator will modulate the speed between 'slow' and 'fast' 😊
When the "Mode" thing was enabled I was wondering why they'd have that, but seeing some other comments, it's a feature to create a natural-feeling breeze apparently, which actually seems like a smart idea, although could be annoying if I hooked one up to my wall fan that sounds like a damned aeroplane prop when run at full tilt (I currently have it on my stepdown transformer and on Low to keep it quiet!), though said fan does have a big IR window on it which would lead me to believe there is a more money model that actually did have remote controlled functions (or is just a place to hide a naughty voyeur cam)... :P
If I was still running a nano aquarium I could think of some interesting use cases for that module to (crudely) control evaporative cooling of a sump and a freshwater top-up pump.
6:42 - Somebody in China's getting fired. I do this trick sometimes, but you can stick the zener there, so it not only limits the voltage to 5V, in one side, and pass the unused half of the AC, allowing the capacitor dropper to work. Saves one part, and the labor to install it. Use a 5.6V zener, instead of 5.1V, to account for that one diode's drop.
That does reduce the component count by one but it also increases supply ripple. With the capacitor-resistor-capacitor used here and the Zener at the output the result should be fairly smooth DC.
very interesting module. I remember you mentioned it on stream. About the washing machine controller. I found a huge ca 0.7 kw squirrel cage motor in my parents 80s tumble dryer. Wonder how many washers use those instead of universal ones.
I had to look up what the "swamp coolers" mentioned in the comments were. I've heard of evaporative coolers before, but they are never used where I live. We always need less humidity, not more!
That is their main weakness - they are very cheap and use very little energy, but the tradeoff is they introduce moisture. A simplest swamp cooler is just rugs sitting in a tray of water, or a water bottle dripping on a rug. Water aggregate state change is very energy-intensive, thus evaporating water has to reduce the temperature rather significantly. In very dry very hot places it's good enough, or at least better than nothing. With very dry climates it is even advantageous to add moisture to prevent static electricity buildup. You need airflow though unless you want entire home turning into sauna..
I think they could still be used in a split system. If the evaporative cooler is outside and connected indoors with coolant pipes you can cool indoors while keeping the humidity outside.
Interesting to note that the buzzer takes on a more "pulsed" sound when more LEDs on the control panel are lit, somewhere there's a component that's struggling to supply enough current! When I've used units similar in actual fans I always assumed it was the beating of the blades making the buzzer sound funny, not the multiplexing of the LEDs!
The SKQ model number is in the Seiko font
Have you considered printing out a plastic vise that clips on to the edge of the work bench? Not sure how far that'd have to reach to be in frame.
In my younger days we called that type of cooler a "swamper" and they used excelsior for the wet element. Smelled like a swamp if you didn't keep em clean.
Various companies producing movies or shows would really love a universal fan controller, but for a different meaning of the word ‘fan’
Nice find! I have two dead swamp coolers that are in need of new controllers
You had me at Triac. ❤️💙
When you had the board plugged in and you were pointing i was thinking "my God Clive watch your finger's that board is live" 😮
I could think of other uses for something like this.. it's able to switch a good few different things and had a timer too. The language barrier is worrying coz iv an awful habit of getting something and then going into a different project and forgetting about other things i wanted to try. Finding the parts i bought and thinking "what's this circuit board for again" and that having Chinese all over id be a while trying to remember.. i also have that electronic hobbyists curse of buying stuff you don't need or will ever use but never think "that was a waste of money"🤔🇮🇪🙏
In a lot of these, the moose is either normal steady died or a kind of changing speed that is supposed to emulate wind gusts
I just gotta admit this..
Your instructions are MUCH better!
That did make me almost spit my Bai at you LOL
After watching this video and reading the comments, I can see me using something like this to control a bunch of stuff here. I need a remote for an infrared heat lamp in the bathroom. Being able to turn it on and off while wet with a remote would be heaven!. We always swap those horrible LED lights for halogens when we move in. Also, we have shittee baseboard heaters which I can't tolerate since they take forever to heat up and forever to cool down.
We also have a nice in the wall "space heater" that has a useless thermostat (37 minutes to shut off). Having a remote to change it on or off from bed or the couch is something I was already planning.
I think they include a classic water level switch with faston terminals because many OEM switches now use tiny connectors with random pinouts and some are even low voltage DC.
Big Clives instructions are always better 😊
A contactor would make this into a full-fledged air conditioning controller.
Hi clive a happy new year to you. Could you please one day show how you do the reverse engineering? We only see the painted picture but I'm curious to see once how you do it. Thank you for teaching and explaining this much. Keep it up 🙂 thanks
a chip with no name? Im shocked. 🤣
That its not just a COB.
Its nice they coated the tracks, but I dont think I will be using one to repair anything on 240v ac. Interesting video 2x👍
Hmmm that might explain why YT randomly suggested I watch a guy installing a generic control board in a washing machine in Hindi(?) a few weeks back.
Yeah, there's a good chance I was watching a few similar videos.
I got that same video about 2 weeks ago myself
So "standard" air conditioners in the UK are water evaporator type? I would have thought that the UK would be too humid for evaporation cooling.
It is too humid for them. But they still sell them.
The mode button is designed to simulate a natural breeze. I've had remote controlled fans before with that function. I never used it, it was very annoying listening to the fan constantly changing speed, and pretty pointless imo.
I think the Mode button activates what in certain fan is called "night mode", setting the fan at high speed at the extremes of the swivel points and low in the middle point, so you can orient the fan and don't get a full direct blast of air when sleeping. Just guessing.
That's really clever. Something that I would definitely want on a hot night.
What Clive forgot to mention is that his IRL fan controller is a tazer that he carries so that he can walk around the city in peace.
Could you please make a video on those US-52 AC Motor Speed Controllers?
They are ment for washing machine motors with tachogenerators. Common type.
Should be very interesting.
Nice one Clive. Cheerz.
. ; )
The "gives it direction" capacitor can be a bit better descrived as giving the initial field which is then pushed against by the 'working' field.
My uncle repairs TVs. He uses this kind of replacement boards for LCD backlight drivers etc.
I like the universal TV repair modules.
As you noted; the LEDs are multiplexed so I would not expect the module's current consumption to change drastically when the number of LEDs lit varies. Instead the TRIAC drive must be simultaneous and 100% duty cycle so would expect the number of TRIACs ON to dominate the current consumption. To an extent you could hear the quality of bleep change slightly when you switched on more outputs.
BTW: What was the rail voltage under minimum load ? Did it ever reach 5V ?
It peaked at just over 5V.
If you hold multiple buttons you can get more LEDs to light!
I bet you could use the pump and swivel parts for anything like a light and usb charger
I'm just starting to understand electronics (the School of Clive is strong), but I'm a little lost on the power supply here. If the local 5v rail is actually the live connection, half wave rectified, does that mean that the +5v rail, referenced to earth, is 240v and the local 0v rail is 235v referenced to earth? I vaguely understand switch mode PS, but this design is new to me.
The 5V is referenced directly to live and the circuits zero volt reference is 5V below that. It might make more sense imagining a 5V battery with its positive connected to a live wire.
LOL Bigcclive in Electroboom-Mode 🤣
the Chinese modular market is amazing one dollar free shipping across the pond!
Happy new year 🎉🎉🎉🎉🎉
Hi Clive: How is the speed of an oven fan controled? The one in my oven looks fine, and runs smoothly, but now and then it does not run up to full speed until given a thump. First time I found this out was when the heating element blew, and I very nearly blew a second soon after, but was lucky enough to smell overheating in time. Very expensive little fault.
The motor looks simple and robust, with nicely self aligning ball bushes at each end, but I'm fed up trying to find thicker and thicker self tappers for the cover, every time I take it out to have another puzzle over what makes it speed up, and why it doesn't always work.
I wish I had discovered your channel years ago. I fear I will never be able to catch up now! My life seems to have been almost entirely spent just fixing one thing after another: anything that can break down always does so as soon as it comes near me! It does teach me stuff, but I'd have liked a normal life too! :/
Check the fan is spinning freely. It may be getting sticky over time and only running when things have started heating up.
@@bigclivedotcom Thanks Clive. I've stripped it down and cleaned it several times, and balanced the fan blades. At first it was a bit tricky getting the armature to run dead centre, till I realised that just tapping the spindle while it was running that lined up the bushes, but there is no noticeable friction once it's lined up. I replaced the wire connector shrouds that had gone brittle and dark from oven heat (I use it quite often on high setting for bread making, which may perhaps be more harsh treatment than basic home ovens usually get. ) I was just puzzled at how the two speeds are obtained without any obvious way of setting them, in the external controls at least. I thought it might have to hit some magic combination of speed and field strength in the right place at the right time, to give it a continuous acceleration up to the design speed. Tempting to give it shots of silicone oil spray, while moving, but you really don't want that smell in your dinner! :)
Do I understand correctly, that they use Triacs (and not MOSFETs) because they switch AC?
Yup... Generally speaking, Triacs for AC and MOSFETs for DC. Though, you can use two back to back MOSFETs to switch AC as well.
just happened to be thinking about how i could regulate the new AC fans i found intended for trash.
Cofan 230V AC / 36W .. usually i'd go with 120mm PC fans and use pwm.
Until now it was easier+cheaper to just get the "honeywell HT900E" to blow a/c-cooled air through my apartment..
The fans on the box look like regular floor models. Maybe if you put them next to the air conditioner they'll work better...?
Do you think this is offered in the United States voltage? It would be interesting to see if the design is exactly the same. 😒
Some are advertised as working from 120 to 240V. With a capacitive dropper it would be fairly easy to adapt it to 120V with a different capacitor.
Guess you could drive a contactor with that cooling output to control a compressor in a bigger unit, and maybe put a bimetallic temperature switch in place of the float switch.
I have an industrial fan in the workshop with a similar control (single winding so there is only one triac), the mode button is called "breeze mode" on my remote and it changes between a sequence of speeds. An absolutely useless feature, driving a 250W motor with a triac is already loud enough without it shifting all the time. The way they control the LEDs and switch buttons is strange to say the least.
Oh great, the control panel is encased in thin cheap plastic and it runs at 240V, what could possibly go wrong.
It could be so much better. Re-arrange the capacitive dropper to the live and couple to the triacs with optocouplers.
don't forget the 0.1mm/28AWG IDE-cable-like ribbon wires.
Those are surprisingly rated 300V but I certainly wouldn't be the one to test it on myself...
The control circuit (buttons, etc) are still live..if they become leaky. due to moisture/ dirt buildup etc.
Thanks Clive very interesting 😊
This will go perfectly with my K40 laser cutter - that thing probably isn't safe to use, either! 🤣🤣
Having seen this unit on the Patreon stream I thought it would be useful, modified, to control a fan/light I had seen where the remote control was missing.
Unfortunately when the fan/light unit arrived I found that not only was the remote control missing, it seems that the light panel has also been removed along with the wiring for it and the power supply for the fan. The seller is going to search for the missing parts but I suspect that his source had removed the missing parts. I'm expecting I will get a refund from ebay.
Sir,, i subscribed today.., again?
Anyways have you or do you know how the soft start wotks on these very exspesive power cords. They limmit start up currant. I havr not found anyone expanding what they acualy do....
Thanks for your work. I find it very helpful..
The simplest inrush limiter is an NTC thermistor. But the more advanced soft starts seem to use a ramped phase angle control.
I feel VERY comfortable with the Hyncdz-branded electrolytic capacitor. NOT!
As others have noted, "Mode" is likely a simulated breeze, using random-ish on/off and fan speed cycles to feel more like a natural breezy day instead of a non-stop blow. I personally don't like that "feature," but I can see some might prefer it.
I have a fan that does that same "mode" function they call it "Breeze" to simulate being outside.
Most of the fans I had to replace the motor was what failed by being gummed up, not the electronics. Lost many nice remote controlled fans that way.
Thanks :)
Mmmmm - because the first thing you think when you encounter a ribbon cable is - ooo - that might be at mains voltage.
I THINK (not shouting, no italics available for commenting that I have figured out) that if all three speeds were to be turned on at the same time, electrically the motor should see it as a single feed to LOW. BUT all three triacs must be switching at EXACTLY the same time in the waveform. I would have to set up an experiment to prove that, but at least in my mind that's how it should work. (I am also assuming that the motor coil is a single tapped winding. If it is multiple coils then my theory would not be correct.) Maybe Clive could scare up a three speed motor and use some simple switches to test the theory out.
it is very confusing: _ _italic text_ _ (remove spaces between "_" and next/previous letter)
That's not how it works. The main motor winding is a single tapped winding but because of the core it also works as a step-up/step-down transformer. If you energize the "low" tap at 120v you will see perhaps 80v on the "high" tap, and on this same motor if you put 120v into the high tap you'd see 180v on the low tap.
If it weren't for the transformer action (for example if it was a tapped resistance wire) then you could indeed connect multiple taps to power.
You also can find:
Universal washing machine control board
Ultrasonic Cleaner Controller board
Lots of music ampifire board😂
I would love to understand why it can't use a bridge rectifier. You said one leg is referenced to the mains. Why does that prohibit a bridge rectifier?
For the TRIACs to be triggered properly the common of the DC control circuit needs to be directly connected to the common of the AC supply. With a bridge rectifier there is by necessity a diode in the way.
@@eDoc2020Thank you so much!
Please ser link to this item.
I need to replace the controller in my fan that water got into and let the smoke out