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  1. #1
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    How do you trigger a triac?

    I have the following circuit with some minor variations:

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    AC voltage is 24V
    Vg is 5V
    R is 390 ohms
    There is a solenoid valve in place of the lamp.
    Triac is MAC97

    But the circuit does not work regardless of whether I connect R to 5V DC or GND.
    The triac won't turn on.

    So how do you turn a triac on?

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  2. #2
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    Re: How do you trigger a triac?

    Please get the data sheet and find which is the guaranteed trigger current.
    As is, you are supplying about 7 mA, and unless it is a sensible gate Triac, the trigger current may be 10 mA or higher.

    Also, unless the Triac is specified for 4-quadrant operation (again look into the data sheet), the Triac will trigger better with minus 5 volts.
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  3. #3
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    Re: How do you trigger a triac?

    Should work with MAC97. Either the real circuit is different from schematic or the part is defective. Did you already check circuit voltages with a multimeter? What do you see?



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  4. #4
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    Re: How do you trigger a triac?

    Also;
    make sure you have not swapped MT1 and MT2.....this is a common beginners mistake.
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