How to test a triac

Posted on Feb 6, 2014

A multimeter can be used to test the health of a triac. First put the multimeter selector switch in a high resistance mode (say 100K), then connect the positive lead of multimeter to the MT1 terminal of triac and negative lead to the MT2 terminal of triac (there is no problem if you reverse the connection). The multimeter will show a high resistanc

How to test a triac
Click here to download the full size of the above Circuit.

e reading (open circuit). Now put the selector switch to a low resistance mode, connect the MT1 and gate to positive lead and MT2 to negative lead. The multimeter will now show a low resistance reading (indicating the switch ON). If the above tests are positive then we can assume that the triac is healthy. Anyway this test is not applicable triacs that require high gate voltage and current for triggering. This is another approach for testing a triac. Almost all type of triacs can be tested using this circuit. This circuit is nothing but a simple arrangement to demonstrate the elementary action of a triac. Connect triac to the circuit as shown in circuit diagram and switch S2 ON. The lamp must not glow. Now press the push button switch S1. The lamp must glow indicating the switching ON of triac. When you release the push button, you can see the lamp extinguishing. If the above tests are positive you can assume that the triac is healthy.

Leave Comment

characters left:

Related Circuits

  • New Circuits



    Popular Circuits

    Balanced Line Driver & Receiver
    Data Switch with LED
    Power-switching circuit
    Broadband frequency doubler
    Motor driver L298 Circuit Schematic Diagram
    LED Audio Level Meter Circuit Schematic Diagram
    Digital Voltmeter and Ammeter Circuit Module
    high frequency waveform generator
    Cimbali D/1 circuit hack
    ISL88731 SMBus Level 2 Battery Charger
    Super Buffer for Guitars