AC Powered PIR 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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High Current Transformerless Power Supply. Home Utility Circuit 24


strip-led-1The serious drawback of the Transformerless power supply is the low current  at the output. So we can’t drive loads that require more than 75 mA current, mainly High watt LEDs and Relay driver circuits. As a rule, 75 mA current will be available per uF capacitance. But this is theoretical and in practical situation, it will be less than 75 mA, because of the low input voltage, quality of capacitor etc. But we can increase the output current to 400 mA or higher using this circuit. It can be used to light High power LEDs, Relay driver circuit etc. One condition is must. The circuit should be enclosed in a shock proof case without any contact point outside the case. Such circuits should not be used as External battery chargers since the output is at mains potential.
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Mains Flasher. Home Utility Circuit 12


1CImagine how much electricity wastage occurs when the Electric Iron or Water heater left switched on for many hours unknowingly after the use. Don’t worry; hook up this tiny circuit in the existing Socket where the device is connected. It will flash brilliantly and reminds you to switch off the device after its use. Its cost is just Rs.10 but it saves hundreds of rupees. Probably, this is the simplest LED Flasher that operates in Mains. Check it
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LED Bulb Hacked. Home Utility Circuit 8


LED-BULBWe all use LED bulbs today to save energy. Different types of LED bulbs ranging from 3 Watts to 15 Watts are now available at low cost. The LED bulb has an array of serially connected 0.5 watt Chip LEDs and a small capacitor power supply. We can also easily make the LED bulb. Let us see what is inside the LED bulb and the circuit operating it.
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