Typical circuit for welding equipment
shown on the following circuit diagram. Turn on delay can be controlled
accurately with Potentiometer P2. We can discharge C1 at each line zero
voltage using DB1 diode bridge and R6-R7 resistors. The voltage charge
will be reset at each new half line cycle and the turn-on delay will be
maintained the same.
Through both potentiometers, the Transil reduces power dissipation. Here’s the circuit diagram:
Note: Transil is a transient voltage suppression diode trademarked by STMicroelectronics