AC 220V 4000W SCR Dimmer Motor Speed Controller
SCR are generally used in AC power control circuits such as lighting dimmers, AC motor speed controls, heaters etc. where mains (line) voltages are used for loads of many watts, or often kilowatts. The aim of AC Control is to trigger the SCR part way through each AC cycle so that the load current through the SCR is switched off for part of the AC cycle, so restricting the average current flowing through the SCR, and hence the average power delivered to the load.
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