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    Controlling 3000W heater using Triac.

    Hi all...
    i am making a small project where i need to just ON and OFF 3000W heater using a triac and 89S52.
    attaching a circuit diagram. Kindly request you to please check the circuit and components and let me know if any changes have to be made.
    as i need to play with high current, so before putting it into use i need to reconfirm and check if the circuit is perfect.

    •   Alt17th February 2017, 06:07

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    Re: Controlling 3000W heater using Triac.

    Current throu led should be limited. Add resistor between optocouple and transistor.
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    Re: Controlling 3000W heater using Triac.

    Hi,

    There are ready to buy isolating solid state relays.
    Use one with zero cross acting.

    Klaus



    •   Alt17th February 2017, 08:34

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    Re: Controlling 3000W heater using Triac.

    Quote Originally Posted by Easyrider83 View Post
    Current throu led should be limited. Add resistor between optocouple and transistor.
    Thanks...
    One more thing i would like to ask... That when the triac is kept off.. i mean when the heater is off... Will some amount of current will flow through the triac, or it will be completely off...



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    Re: Controlling 3000W heater using Triac.

    Yes, there will be some small current. If you care about human body protection, mechanical relay will be better option.
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    Re: Controlling 3000W heater using Triac.

    Since you are not using a snubber, the leakage current will be very small....but the circuit could still give you some tingles.

    A mechanical relay, as advised previously, will completely cut off the power.
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    Re: Controlling 3000W heater using Triac.

    If not a ready-made solid state relays, you'll use zero switching MOC3041 instead of MOC3021 with your triac.



    •   Alt17th February 2017, 16:15

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    Re: Controlling 3000W heater using Triac.

    Use MOC3063 zer crossing optotriac. No need for a transisitor at the input side of the opti-triac. Can be directly driven with micrcontroller with a current limiting resistor.



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