OBJECTIVES :
To draw the VI characteristics of " TRIAC "
Apparatus Required :
| S.No | Apparatus | Specification | Quantity |
|---|---|---|---|
| 1 | Ammeter | 0-10mA | 1 No |
| 2 | Ammeter | 0-20mA | 1 No |
| 3 | Voltmeter | 0-30 V | 1 No |
| 4 | RPS | 0-30 volts | 2 No |
| 5 | Connecting wire | 1 K ohm | 1 No |
Theory :
A ' TRIAC ' is a 4 layer ( P - N - P - N ) device however it can conduct in both directions its terminals are denoted as T1, T2 and G ( or MT1 ) and MT2 & G ) it conducts when either of there terminals is positive with respect to the other. moreover it can be triggered by a gate signal which is either positive/negative with respect to T1 thus it is equivalent to two thyristors connected in antiparallel when a TRIAC has been triggered the gate terminal becomes ineffective when conducting the voltage drop across it is very small and current in the circuit has to be limited by a resistance connected in the circuit it is very convenient to use a matched DIAC for triggering a TRIAC
PROCEDURE:
1. Keep the potential divider at the minimum voltage position and variable resistance in the TRIAC circuit at about 70.
2. Adjust the gate circuit current to 25 mA.
3. Va the voltage applied to TRIAC and record the anode voltage and anode current readings
4. Plot the VI characteristics.
5. Repeat with terminals T1 & 12 interchanged.
Result: -
obtained VI characteristics of TRIAC
| S.No | VAK | IAK |
|---|---|---|
| 1 | ||
| 2 | ||
| 3 | ||
| 4 | ||
| 5 | ||
| 6 |
