dapu
Junior Member level 3
I was trying to switch some AC appliances (Ceiling fan 75w, LED bulbs etc.)
Till now I had tried switching using BT136, but I am planning to take it to another level. So this is what I came up with so far,
1) I will need a MOV for over voltage.
2) Snuubers on triac and gate
3) Some inductor to supress transients further (I am still reading about it, on what value to use and how to select one)
4) a fuse
5) an optocoupler
But after figuring out all these, I decided to cut down on BOM, so I searched for and came across these
Snubberless Triacs/ Hi com triac/ 3 quadrant triacs which claim to be not affected by line transients since they dont switch in 3rd quadrant and they are having high dv/dt tolerance. So I can cut down on both snubber circuits.
ACST - they claim to have over voltage potection built in so I can exculde MOV and snubber both and also they claim that it can be triggered directly from MCU as they also include some sort of gate protection (correct me if i got that wrong)
Which one should I choose from? ACST are extremely costly as compared to standard triacs. 3 quadrant triacs are still somewhat reasonably priced. But again I am not sure with latter what exactly can I omit? Is it only Snubber on gate or on triac?
Sorry if it is bit confusing, but in short..I am looking for some advice on what to go with and what not. What is best way to not compromise with safety and also reduce BOM. I am planning to use it in my house with approx 6 triacs on board.
Other details:
I am planning to drive triac or optocoupler with a HC595 register or MCU
thinking to use transformerless power supply to trigger gates of triacs.
Its 220V mains
Till now I had tried switching using BT136, but I am planning to take it to another level. So this is what I came up with so far,
1) I will need a MOV for over voltage.
2) Snuubers on triac and gate
3) Some inductor to supress transients further (I am still reading about it, on what value to use and how to select one)
4) a fuse
5) an optocoupler
But after figuring out all these, I decided to cut down on BOM, so I searched for and came across these
Snubberless Triacs/ Hi com triac/ 3 quadrant triacs which claim to be not affected by line transients since they dont switch in 3rd quadrant and they are having high dv/dt tolerance. So I can cut down on both snubber circuits.
ACST - they claim to have over voltage potection built in so I can exculde MOV and snubber both and also they claim that it can be triggered directly from MCU as they also include some sort of gate protection (correct me if i got that wrong)
Which one should I choose from? ACST are extremely costly as compared to standard triacs. 3 quadrant triacs are still somewhat reasonably priced. But again I am not sure with latter what exactly can I omit? Is it only Snubber on gate or on triac?
Sorry if it is bit confusing, but in short..I am looking for some advice on what to go with and what not. What is best way to not compromise with safety and also reduce BOM. I am planning to use it in my house with approx 6 triacs on board.
Other details:
I am planning to drive triac or optocoupler with a HC595 register or MCU
thinking to use transformerless power supply to trigger gates of triacs.
Its 220V mains
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