I try to design a PCB for home Automation,
so I use IR receiver and remote,
microcontroller (Atmega328),
TRIAC (BT136),
Optocoupler (moc3021)
Circuit Diagram
IR Remote Control Sch.pdf (111.8 KB)
Board
IR Remote Control Board.pdf (19.2 KB)
kicad 3d View
Pleas add snubber circuit on MT1-MT2 of triac. Especially if the load is inductive.
Thank you sir,
I add Snubbar Circuit.
New schematic diagram With Ac Dimmer and snubber circuit,
@jtd @Ashish_Pardeshi @karnamdpdurga @ravi312
sch.pdf (127.7 KB)
Nicely done schematic.
I cannot see the snubber capacitors on the board. What is their rated voltage?
Also the snubber resistor, what is the rated voltage and wattage.
I recently purchased a fan dimmer from amazon - too tied up to make one. The device started misbehaving. It would not turn on the fan when the pot was kept at lower speed. But once the pot crossed about 50% the fan would run full speed.
The pot itself was ok. But the snubber resistor had arced. It was an open resistor. Such arcing is happens when ordinary resistors not rated for 600V operation are used in mains circuits.
How does one get 600v in a 230v supply?. 230v is the rms rating. 325 is the peak and 650 v is the peak to peak. If you have an inductive load you will see a peak voltage of 600 V. That is why semiconductor switching device for mains operation have to be rated at atleast 650V.
If the snubber resistor is open, the triac can misfire due to dV/Dt effects - no gate current but device turns on - depending on phase angle. dV/Dt effects are caused due to internal parasitic RC elements of the thyristor.
