|Building a Simple Dimmer Circuit
In this example a potentiometer is controlling the firing point of the
triac. Capacitor C4 is charged via resistors R3, R4, P1, and R5. After
a certain time, dependant on the potentiometer, the charge contained
in C4 is large enough for the dimmers diac D to start conducting, so that a firing
pulse is applied to the gate of the triac. Consequently the triac conducts
and power is transferred from the dimmer to the tungsten or LED lamp.
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