0
\$\begingroup\$

I am working on an IoT project to control the speed of my ceiling fan through my mobile.

The problem is that the TRIAC and the fan speed circuit just won't work when it is on a PCB. I know it sounds weird but I don't know what's going on. First I prototyped the whole circuit on a breadboard. It worked and I began to work on a PCB. It worked for a day and then all of a sudden stopped working, though I did notice the TRIAC getting quite hot as soon as I powered it up driving an inductive load for test (a piston pump used in soldering iron stations.)

Then I took the whole circuitry out, reconfigured it, and found that I was missing a snubber circuit which miraculously made my circuit work again and I could dim the speed once again. I still don't understand this, because conventional cheap dimmers work without any.

Long story short, it worked for some time just like the previous time and now it is just stuck again. It won't work as I intended it to. I don't have an oscilloscope to see what is really going on down there.

Previously when the circuit went bad without the snubber, the TRIAC got extremely hot and the pump worked on full voltage, but now the TRIAC gets a little warm and it's as if you are powering the pump with 20 VAC. The circuit diagram is given below.

enter image description here

\$\endgroup\$
5
  • \$\begingroup\$ Welcome! At the very least, rotate your image. Ideally, click on edit and the schematic symbol. From there you can draw your schematic. Use schematic symbols, not package pinouts. \$\endgroup\$ Commented Nov 6, 2023 at 12:19
  • \$\begingroup\$ Hi and welcome to EE! I don't know if you're familiar with and uses any EDA program, but if you do, a big help for us and for you is to draw schematics that you can upload. But @winnys suggestion is even better since it allows for interaction by EE's users as well. \$\endgroup\$ Commented Nov 6, 2023 at 12:21
  • \$\begingroup\$ Sure ill keep that in mind. \$\endgroup\$ Commented Nov 6, 2023 at 12:25
  • \$\begingroup\$ Which optocoupler do you use in the trigger circuit? Are pin 4 and 6 swapped? \$\endgroup\$ Commented Nov 6, 2023 at 14:22
  • \$\begingroup\$ Its an moc 3021 \$\endgroup\$ Commented Nov 6, 2023 at 22:55

0

Reset to default

Start asking to get answers

Find the answer to your question by asking.

Ask question

Explore related questions

See similar questions with these tags.