My Light Diagram

The AC power line indicator presented here has a complete galvanic isolation from the grid. The indicator is an LED that lights up when a current flows, although the current can be measured more accurately with an AC voltmeter set to its mV range. The detector is a transformer taken from an old  mobile phone charger. The value of the secondary isn't important because we only make use of the primary 230 V (115 V) winding. The (extension) cable through which the current has to be detected should have  an  as  short  as possible  section  of its outer insulation removed. The wires should then be moved apart. The blue wire should be placed on top of the transformer and the brown wire underneath, or the other way round. The brown and blue isolation shouldn't be removed, so there is no danger of the AC line voltage becoming exposed.lf there is a green/yellow wire as well, this can be placed on either side of the transformer. The brown and blue wires should be in parallel with the wi...

Varying Brightness AC Lamp Circuit , an SCR is used to slowly vary the intensity of a 120 volt light bulb by controlling the time that the AC line voltage is applied to the lamp during each half cycle. Varying Brightness AC Lamp Circuit Diagram Caution: The circuit is directly connected to the AC power line and should be placed inside an enclosure that will prevent direct contact with any of the components. To avoid electrical shock, do not touch any part of the circuit while it is connected to the AC power line. A 2K, 10 watt power resistor is used to drop the line voltage down to 9 volts DC. This resistor will dissipate about 7 watts and needs some ventilation. Operation: A couple NPN transistors are used to detect the beginning of each half cycle and trigger a delay timer which in turn triggers the SCR at the end of the delay time. The delay time is established by a current source which is controlled by a 4017 decade counter. The first count (pin 3) sets the current to a minimum whi...

Principle of Phase Angle Control Top - Output Voltage Bottom - Gate Drive Signal Image source: Wikipedia (http://en.wikipedia.org/wiki/File:Regulated_rectifier.gif) The photo above clearly illustrates phase angle control: output voltage controlled by the gate drive signal applied to a thyristor. What is phase angle control? That is what I'm going to talk about in this article. Phase angle control is a method of PWM applied to AC input voltages, usually the mains supply. Of course, the AC supply could be from a transformer or any other AC source, but the mains supply is the most common input – this gives the phase angle control method its greatest usefulness. It has of course become quite obvious from the title (and I’m sure most of you reading will already know this) that the purpose of phase angle control is to control or limit power to the load. The power device used in phase angle controllers is a thyristor – mostly triacs or SCRs. (There are methods of phase controlling employi...

This DC-to-AC inverter schematic produces an AC output at line frequency and voltage. The 555 is configured as a low-frequency oscillator, tunable over the frequency range of 50 to 60 Hz by Frequency potentiometer R4.  The 555 DC-to-AC Inverter Schematic The 555 feeds its output (amplified by Q1 and Q2) to the input of transformer T1, a reverse-connected filament transformer with the necessary step-up turns ratio. Capacitor C4 and coil L1 filter the input to T1, assuring that it is effectively a sine wave. Adjust the value of T1 to your voltage. Error fix: Pin 7 and 2 were reversed. Original pinout was correct. Parts List: R1 = 10K R2 = 100K R3 = 100 ohm R4 = 50K potmeter, Linear C1,C2 = 0.1uF  C3 = 0.01uF C4 = 2700uF Q1 = TIP41A, NPN, or equivalent transistor Q2 = TIP42A, PNP, or equivalent transistor  L1 = 1uH T1 = Filament transformer, your choice The output (in watts) is up to you by selecting different components. Input voltage is anywhere from +5V to +15Volt DC, ad...

This circuit diagram will detect AC line currents of about 250 mA or more without making any electrical connections to the line. Current is detected by passing one of the AC lines through an inductive pickup (L1) made with a 1 inch diameter U-bolt wound with 800 turns of #30 - #35 magnet wire. The pickup could be made from other iron type rings or transformer cores that allows enough space to pass one of the AC lines through the center. Only one of the current carrying lines, either the line or the neutral should be put through the center of the pickup to avoid the fields cancelling. I tested the circuit using a 2 wire extension cord which I had separated the twin wires a small distance with an exacto knife to allow the U-bolt to encircle only one wire. AC Line Current Detector Circuit Diagram The magnetic pickup (U-bolt) produces about 4 millivolts peak for a AC line current of 250 mA, or AC load of around 30 watts. The signal from the pickup is raised about 200 times at the outpu...

Description                A lot of students are who don't know how to convert 230 volt AC to 400 DC. So today i am published  ' 230 V AC to 400 V DC circuit diagram ' on my blog. Working principle of this circuit diagram is very simple. You already knew the working principle of a bridge rectifier. This circuit is same as bridge rectifier and the working principle is also same. The fuse is used to protect the circuit, if the current is greater than 1 A. Parts List Component No: Value F1 1 A B1 IN4007  C1 470MF/450V  V1 230 V AC  Source

Here i am presenting you a 230V LED Driver circuit without transformer . Here i am using 5 led's you can increase the count at your convineance. Due to the absence of Transformers we can reduce the cost and size of the circuit considerably. As we all know LED's are Cheap, efficient and cool device with low power consumption. So we can reduce our electricity bills to a great extent. The circuit is powered by 230V 50Hz ac supply , so be careful while troubleshooting this project. Led's commonly works only in DC, so we have to convert the alternating current to direct current and step down to a safe value before applying to the led sequence. The circuit mainly consisting of 5 led bulbs, a bridge rectifier and a filtering network with voltage regulator. Read More.....

Description This circuit will detect AC line currents of about 250 mA or more without making any electrical connections to the line. Current is detected by passing one of the AC lines through an inductive pickup (L1) made with a 1 inch diameter U-bolt wound with 800 turns of #30 - #35 magnet wire. The pickup could be made from other iron type rings or transformer cores that allows enough space to pass one of the AC lines through the center. Only one of the current carrying lines, either the line or the neutral should be put through the center of the pickup to avoid the fields cancelling. I tested the circuit using a 2 wire extension cord which I had separated the twin wires a small distance with an exacto knife to allow the U-bolt to encircle only one wire. The magnetic pickup (U-bolt) produces about 4 millivolts peak for a AC line current of 250 mA, or AC load of around 30 watts. The signal from the pickup is raised about 200 times at the output of the op-amp pin 7 which is then peak ...

This circuit will detect AC line currents of about 250 mA or more without making any electrical connections to the line. Current is detected by passing one of the AC lines through an inductive pickup (L1) made with a 1 inch diameter U-bolt wound with 800 turns of #30 - #35 magnet wire. The pickup could be made from other iron type rings or transformer cores that allows enough space to pass one of the AC lines through the center.  Only one of the current carrying lines, either the line or the neutral should be put through the center of the pickup to avoid the fields cancelling. I tested the circuit using a 2 wire extension cord which I had separated the twin wires a small distance with an exacto knife to allow the U-bolt to encircle only one wire. AC Line Current Detector Circuit Diagram The magnetic pickup (U-bolt) produces about 4 millivolts peak for a AC line current of 250 mA, or AC load of around 30 watts. The signal from the pickup is raised about 200 times at the output of th...

This circuit uses low-voltage AC to drive a string of 50 or so bi-color LEDs (two LEDs connected in inverse parallel). Power to the LEDs is controlled by the Triac and the two optocouplers which have their photo-transistors effectively connected in inverse-parallel. Depending on which optocoupler is turned on, the Triac applies positive, negative or both half-cycles to the LEDs and so the colours can be red, green or in-between. Switch S1 is used to select the pulses from two oscillators which are formed by the NAND gates in IC1 (4011B). This provides a variety of LED flash patterns, depending on the setting of S1. Circuit diagram: Author: Matthew Peterson - Copyright: Silicon Chip Electronics

Description    This circuit is not a novelty, but it proved so useful, simple and cheap that it is worth building. When the positive (Red) probe is connected to a DC positive voltage and the Black probe to the negative, the Red LED will illuminate. Reversing polarities the Green LED will illuminate. Connecting the probes to an AC source both LEDs will go on. The bulb limits the LEDs current to 40mA @ 220V AC and its filament starts illuminating from about 30V, shining more brightly as voltage increases. Therefore, due to the bulb filament behavior, any voltage in the 1.8 to 230V range can be detected without changing component values. Circuit diagram:  Parts: P1 = Red Probe P2 = Black Probe D1 = 5 or 3mm. Red LED D2 = 5 or 3mm. Green LED LP = 1220V 6W Filament Lamp Bulb Note:    A two colors LED (Red and Green) can be used in place of D1 & D2. Source http://www.extremecircuits.net/2009/08/dc-or-ac-voltage-indicator-circuit.html

This general-purpose low-power (5 W) audio amplifier is suitable for driving a spaker 5W Audio Amplifier With Ac Power Supply Circuit Diagram of approximately 8 to 12 inches. A Sanyo LA4460 IC is used as the audio output IC. The circuit consists of a loudness control, driver amplifier Ql, and bass and treble controls of about ±10 dB boost/cut. It should be useful in a wide variety of situations. Either the ac supply shown can be used, or a 12 Vdc supply can be connected to points A&B (positive) and C (negative). Two of these circuits, using ganged potentiometers at R2, R7, and Rll can be used for stereo applications. T1 is a 12-V 1-amp plug-in transformer. Notice that IC1 must be heatsinked. Power output is about 5 W. A 4` 2` 0.050` aluminum heatsink should be adequate .