When we use Triac and LDR to make Automatic Lights, a major problem arises . Lamp starts flickering during the light transition period in the evening and morning. Lamp fully turns on only when there is complete darkness and turns off only when day light is full. This simple design solves the problem. Light instantly turns on / off without any flickering. You can drive CFL, LED bulb etc which turns on automatically around 6 pm and turns off around 6 am. See the simple design. Continue reading “Flicker Free Automatic Light”
A Simple design of PIR Light using Tranformerless Power Supply and Triac for driving the load. Too compact and can be enclosed in a small case. The light turns on when the PIR sensor detects human movement and turns off after the preset time. Re triggers in another movement. Its range is 30 cm to 10 meters and time delay, 30 seconds to 3 minutes both can be adjusted using the presets in the PIR sensor Module.
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Wireless Electricity Generator
Here is a High Efficiency Wireless Electricity Generator project. Usually we make a simple wireless electricity generator to light 1.8 volt Red LED. But here the efficiency of the Wireless Electricity Generator is increased to light 1 Watt White LED Bulb that requires 3.6V. It generates voltage and current even to light a Strip LED. Try it and see the wonder of LED lighting without a battery connection.
PIR Sensor Alarm
This simple alarm can be used to detect the movement of human beings at a distance of 10 meters. It works both day and night and beeps shortly when there is a human movement through its detecting range. It is ideal to monitor the entry passages, stair case, corridors etc. It is highly useful to monitor the human movements in Flats, Multi storied buildings, Shops etc. A relay can also be connected for activating lights, electric alarms etc. It can be used as a Personal alarm during journey to protect luggage.
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How to connect Digital Volt Ampere Meter
Digital Volt Ampere meters are now available to measure DC voltage and Current. It can be connected to the output of the Power supply. So the output voltage and current to the load is displayed in the meter. If a battery is connected to the power supply for charging, we can see the current consuming by the battery during charging. When the battery is fully charged, current drops to zero which indicates the termination of charging. If project is connected, the voltage and current to the project is displayed.
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Voltage regulation through Fixed Voltage Regulator IC is the most suitable method.78xx series positive and negative regulators are widely used to get fixed voltage to drive loads. Here explains a circuit design to get regulated voltage from a 12 volt 500 mA power supply .This circuit can deliver 5 volts at 300 mA for driving a load.
The circuit is Voltage and Current regulated and with Polarity and Surge protection components.
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1 Watt LEDs are widely used in Emergency lights and LED lights. Most of the circuits use 4 volt battery having 0.5 to 4 Ah capacity. The 1 watt LED is rated 3.6 volts maximum so we need the correct value resistor for LED to get maximum brightness. Let us see how the LED resistor value is determined.
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