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Are the TRIACs used properly on the basic circuit example below?

Latest Updated:08/01/2005

Question:

Are the TRIACs used correctly in the forwarding/reversing circuit of the motor in the basic circuit example below?

Answer:

If one of the TRIACs is ON and the other TRIAC which has been off switches on in the forwarding/reversing circuit of a motor, a charging loop that charges phase advancing capacitor C1 is created.
As a result, an extremely large pulse current flows through the two TRIACs, damaging them.

To prevent this, limit the discharging current from phase advancing capacitor C1.
It is recommended to insert inductance L in series with C1 as shown in the circuit example below.

Suitable Products
Diodes for Constant Voltage