Pulsed Shot Welding – Handmade
Do not try to repeat this device if you don't know the electrical engineering and electrical safety regulations well! The author does not bear responsibility for the damage that you can cause.
This impulse spot welding works without a transformer and is connected directly to the mains. The energy of the pulse is determined by the capacitance of the storage capacitor and the voltage on this capacitor. Voltage can be monitored with a voltmeter.
Elements of the circuit: Dr1, C3, R4 can be excluded if a high-frequency thyristor is used. But high-frequency thyristors are more expensive than low-frequency thyristors. When choosing a thyristor, one must pay attention to the magnitude of the limiting pulse current. It is desirable that the thyristor can withstand a pulse of magnitude greater than 2000 Amperes.
Pulse energy:
E = C(U*√2)²/2
E – pulse energy (J)
C – capacitor capacitance (F)
U – AC voltage (V)