Important !
This circuit is potentially dangerous ! If your electricity comes with a "live" wire and a "neutral", the neutral is usually connected to the earth. Sometimes there is no neutral at all and you have 3 phase wires, with 115V to 240V between two phases. If you form a conductive path to the earth and you touch one of those phase ("live") wires, this can be lethal !
Only work on a project like this if you know what you are doing, this is nothing for beginners !
Even if you are experienced, you should always use a 30mA drip-switch when working on any project.
This LED can be used as an indicator for any appliance that works on mains tension. Not only does it light up but it will also blink to draw attention. The blinking frequency of the LED depends on the RC combination and wil increase by reducing R1 to half its value or by reducing C1 to 4.7µF. The capacitor’s voltage must be higher than the diac’s breakover voltage.
Bright white LEDs of the 3V - 3.5V type can also be used.
PARTS LIST :
Unless otherwise stated, resistor wattage = 0.25W.
This circuit is potentially dangerous ! If your electricity comes with a "live" wire and a "neutral", the neutral is usually connected to the earth. Sometimes there is no neutral at all and you have 3 phase wires, with 115V to 240V between two phases. If you form a conductive path to the earth and you touch one of those phase ("live") wires, this can be lethal !
Only work on a project like this if you know what you are doing, this is nothing for beginners !
Even if you are experienced, you should always use a 30mA drip-switch when working on any project.
This LED can be used as an indicator for any appliance that works on mains tension. Not only does it light up but it will also blink to draw attention. The blinking frequency of the LED depends on the RC combination and wil increase by reducing R1 to half its value or by reducing C1 to 4.7µF. The capacitor’s voltage must be higher than the diac’s breakover voltage.
Bright white LEDs of the 3V - 3.5V type can also be used.
PARTS LIST :
Unless otherwise stated, resistor wattage = 0.25W.
- R1* = 470KΩ
- R2 = 680Ω
- C1* = 10µF/40V or higher
- D1 = 1N4007
- D2 = LED
- Di1 = diac BR100, ER900