A TRIAC is an component often used to control high power currents, both as a switch and as a "dimmer"-like construction for controlling lamps or electric engines.
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SSR vs optocoupler with TRIAC output
I've designed (and mostly implemented, now) a system for turning on and off 24VAC solenoids. In order to achieve this, I used optocouplers with TRIAC output (Sharp PR26MF1xNSZ series). The datasheet ...
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2answers
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How to calculate minimum gate current and voltage of a TRIAC
I want to use this TRIAC:
http://www.littelfuse.com/data/en/Data_Sheets/Littelfuse_Thyristor_Lxx06xx_Qxx06xx_Qxx06xHx.pdf
but only the maximum Igt and Vgt are given (25mA and 1.3V). How much ...
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Choosing components for a triac's snubber
I'm interfacing the BT139-600 TRIAC with this MOC3051-M Opto-triac. I want to build a snubber circuit for the TRIAC as shown in the MOC3051M opto-triac's datasheet @ page 8, figure 12.
The load ...
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1answer
765 views
Current limiting at mains voltage
I am driving a BTB16-600BW triac using a MOC3052 exactly as suggested in the MOC3052 datasheet:
The current into the power triac gate is limited using the highlighted resistor. My triac requires at ...
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1answer
837 views
Using a triac to switch on/off a single phase AC motor
I want to use a triac controlled by a suitable optoisolator such as a MOC3020 to switch a single phase AC motor on and off, like the ones you'd find in a typical desk fan or a blender or similar.
I ...
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1answer
401 views
Triac Turn-on Stress Calculation
When snubbing a triac, one of the concerns is minimizing turn-on stress as your snubber triac discharges across the newly-shorted terminals of the triac. This paper says that the main concern is ...
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993 views
Sanity-check on snubber design
I keep frying resistors in the following optocoupler and triac snubber circuit, and I'm not sure whether to attribute this to bad design, or to faulty components.
There are no observable sparks at ...
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Why Snub an Optoisolator?
I am using an optocoupler and a power triac to switch 120VAC supply to an ~108 watt fan. The datasheet for my optocoupler requires me to snub the optocoupler output when I'm switching an inductive ...
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3answers
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Controlling High Voltage device with Arduino
I want to control lava lamps using Arduino. I think it shouldn't be hard project, but I have no experience with hardware projects so I'm not sure witch design will feet best for me.
I consider using ...
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1answer
833 views
What's the difference between 3 and 4 quadrant triacs?
I'm looking at triac datasheets, in particular this datasheet for BTA16 series triac. The "electrical characteristics" section is split into two parts: snubberless/logic level (3 quadrants) and ...
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548 views
Are TRIACs symmetrical?
When debugging a circuit using a micro-controller and triac to control AC current I ran into an issue (the triac wouldn't switch off) that was only resolved by flipping the polarity of the triac. The ...
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2answers
605 views
Microcontroller + Triac without an optoisolator
I have a project that needs to be in use on saturday (afterwards I'll be able to complete it properly) and my optoisolators haven't come in yet.
I'm using an arduino to switch mains power (on/off) ...
