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  1. #1
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    how to test a thyristor

    Hi

    I am currently carrying out a damage on battery charger and stumbled on problem as it would not operate. I suspected it was a thyristor and I have no idea how to test it. Two thyristors are in the thyristor bridge circuit configuration with two subbers cicuit fitted across the thyristor respectively. I took the subber out of way and I was not entirely sure how to test it with DMM? Is there any different mehtod of test the SCR module? I look forward to hear from you intelligent guys

    Regards

    MM

    •   Alt13th August 2009, 13:09

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    test thyristor

    A method I've used is:
    Ohms range on the DMM
    + lead to the SCR's anode
    - lead to the SCR's cathode
    Should read infinite if good
    Short the gate to the anode
    Should read low resistance if good
    With smaller SCRs the low reading should remain after the short is removed.
    With large SCRs the reading may go back to infinite after the short is removed, because the DMM current is below the SCR's minimum hold current.

    Ken



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    scr thyristor

    Is there any way to check Triacs which are basically two scr's connected Cathode to Cathode?



    •   Alt14th August 2009, 06:52

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    thyristor testing

    Same way as the SCR...almost:
    + lead to the triac's anode-2
    - lead to the triac's anode-1
    Should read infinite if good
    Short the gate to the anode-2
    Should read low resistance if good
    - lead to the triac's anode-2
    + lead to the triac's anode-1
    Should read infinite if good
    Short the gate to the anode-2
    Should read low resistance if good

    Ken



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    thyristor test

    please, how can i learn effectively how to use TRIAC and THYRISTOR. I have good and practical understanding of bipolar transistors and MOSFET. Any good link or tutorial will be highly appreciated as i intend to use triac with microcontroller to switch 220vac to 240vac to a pump motor without using relays. Can it be achieved?. Finally, what is the difference between SCR and Thyristor and Triac. thanks



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    test scr

    SCRs and triacs are both thyristors.

    You might want to start here:
    http://www.allaboutcircuits.com/vol_3/chpt_7/index.html

    For interfacing microcontrollers with triacs:
    http://www.st.com/stonline/products/...re/an/1863.pdf

    Ken



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    how to test thyristor

    i will check the links and post any doubt here. Thanks for the reply.



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