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  1. 1

    Motor Speed Controller

    Hello, I have an 125 mm angle grinder with 720 W AC motor and soft start (attached pdf document). I want to build a speed controller for this angle grinder. I tested a simple triac dimmer (from the attached jpg schematic) but it doesn't work normally, because it is making a strange buzzing...
  2. throbscottle

    What's going on here?

    Been having a clear out of old files, found this. I captured this bit of schematic when I dismantled an old money counting machine, years ago. It's the power supply to an induction motor which rotates the pick-up rotor. The motor is shown by L1, L2 and the circle. Triac D2 looks like a...
  3. V

    IR based Speed control of Single Phase AC motor using a Microcontroller 8051

    Hi all, My project is to create an infrared remote to change the speed and switch on/off of a cap start/run type single phase induction motor operating at AC mains (230V, 50Hz). I have worked out the controlling the speed of the motor part (using a solid state relay to control phase angle of...
  4. D

    Triac Blowing

    Good Afternoon I am busy building a static VAR compensator for a project and i need to use TRIACS to switch in my capacitor banks. The system is 3 phase 400 VAC and consists of 3 motors with varying loads. There is a system that determines the power factor and switches in the capacitors. Today...
  5. StudentSA

    Optocoupled Triac Help

    Good Day, I am really struggling to get a "simple" Triac circuit to work. I started by consulting the typical application from the optocoupler MOC3043 datasheet: I chose the MOC3043M as is was suggested for 240Vac operation and had the lowest "turn-on" current (5ma). I've constructed the...
  6. Clarkdale44

    What are the alternatives i can use for SL100 Transistor and BT44 Triac?

    Hello I am thinking of building the below circuit but i am short on components. I have all the others except SL100 transistor and BT44 triac which i can't seem to find in any local store. If anyone can tell me what alternative components i can use for these two then please let me know i would...

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