Nr odd k2636 behavior

Having just completed the ac motor controller kit, carefully checking resistor values and component polarity where applicable (I guessed that the non-electrolitic
capacitors were non-polar) I attatched the mains to mains input and my volt meter to the load output and only got between .4 and .2 volts using the potentiomenters. I then attatched a second mains supply to load input and got 118 volts on load output with no variation from potentiometers. I then detatched the mains from mains input and load input and checked resitance in mains input circuit to a value of 742 kilo-ohms. I then tested the load input circuit resistance as 0.L or open. I then tested the load output circuit as 0.L… Just wondering if you could suggest a course of action from these resutls. I have a camera with very poor resoluton so pictures are not very informative. All solder joints appear to be solid and conical. Thanks for any help you may provide,


Without a load connected to the output, all measurements are useless.

I thought those results might mean the triac was malfunctioning. Every complete circuit should show some resistance. I noticed on the schematic than load supply and load out share neutral so I measured between load out live and load in neutral and showed 0.L. Same between load out live and load in live.

No, without load, you can’t interpret these values.
However you said that you also measured MAINS IN? Here you should have a rather low value of a few hundred ohms to only a few K because you have the primary of the transformer there. A high value there means defective transformer, bad fuse, bad solderings, …

I don’t know if you can test the tranny in circuit but I got 110v on two pins and 118 on the other two on the 120 side and 9v between the two outer pairs of pins on the 6v side. The 200ma fuse measures 4v between either side of the fuse block and load out neutral and 120v from either side to mains neutral. I did manage to get some fairly clear pictures of both sides of the board but have no idea how to include them. And I guess you can’t really measure the resistance of the resistors in circuit either. I get wildly fluctuating readings from r13 and several others. So I could wire a light bulb into load out for a load and see what happens.
Just 4 volts to bulb. Well, it looks pretty nice anyway, suppose I can hang it on the wall.

Thanks for your interest,

Sorry, this forum does not allow pics.
You will have to use a free online picture base instead.

a few pics

As always mentioned (but not here): HIGH RES and SHARP pics!
Sorry but these pics are useless. We all here want to help you but please help us by giving us pictures on which we can see something and not crappy-phone-camera style.

I don’t have a phone and I am not going to spend a bunch of money on a camera on the off chance that someone might have a constructive suggestion on trouble-shooting a 40$ fan controller kit.

All those pictures seem out of focus, which is normal for close-up shots taken with the default settings of digital cameras. Does your camera have a “macro” setting to take close-up pictures? … 000091.bmp
thanks for responding. I picked the wrong link in previous post and hope the two above are correct. These are a couple that I took through a large stand-type magnifier. If I look closely I can make out the res bands but some of the lack of clarity may come from tremors from pressing the button. Do these have enough resolution for me to try taking more?

Much better. Now for the soldering side the same please. … 250100.bmp
You may notice a particularly ugly area by the toroid holes. I had to remove it after insertion because the half-hitch securing one of the legs was untied.

Sorry, the quality of the pics does not allow us to spot any errors.
We’d recommend to return the kit for inspection/repair.
If you are a US resident, please call (817) 284 77 85
Rest of the world:

Velleman Projects Tech. Dept.
Legen Heirweg 33
9890 Gavere