My Light Diagram

A very simple DC motor speed controller circuit can be constructed using a LM317 voltage regulator integrated circuit. This DC motor speed controller can be used for speed control  of mini drills or for other small DC motors. This motor controller circuit will provide a large output current. The maximum output current from the secondary turns of the transformer shout provide 1.5 times of the maximum DC output current. The output voltage and the speed (rpm) is set by the P2 variable resistor. DC Motor Speed Controller using a LM317:  As soon as the current drawn exceeds a certain value, T2 will be switched on. This results in a base current for T3 so that R5 is in parallel with R6. This automatically raise the output voltage to counter a threatened drop in rpm.  The moment at which this action occurs is set by P1.

This electronic voltage controlled switch circuit diagram project make a very easy. In this electronic project circuit the 555 timer is used in a novel way, as a voltage controlled switch.  Voltage Controlled Switch Circuit Diagram: Notes: The old and omnipresent NE555 can be very good at something it was not meant for: driving relays or other loads up to 200 mA. The picture shows an example circuit: if the input level rises over 2/3 of the supply voltage - it will turn on the relay, and the relay will stay on until the level at the input drops below one third of the supply voltage. If the relay and D1 were connected between pin 3 and ground, the relay would be activated when the input voltage drops below one third, and deactivated when the input voltage goes over two thirds of the supply voltage. It is also a nice advantage that the input requires only about 1 uA, which is something bipolar transistors can't compete with. (This high impedance input must not be left open.) A large ...

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...

Here is the simple Automatic Night Light circuit using Phototransistor. Components Required: 1) Breadboard 2) 470 ohm resistor 3) 22 Kilo ohm resistor 4) LED (Any Color) 5) Phototransistor 6) 3904 NPN Transistor 6) 9Volt Battery  Procedure: Connect the circuit as shown in the circuit diagram below. During day time the brightness will be more, which forward biases the phototransistor. Therefore the current flows through the collector to emitter of phototransistor. Hence there is no base current to forward bias the 3904 NPN transistor and the LED remains OFF. During night time the brightness goes down, which cannot forward bias the phototransistor. Therefore the current will not flow through the phototransistor. Hence there is enough base current to forward bias the 3904 NPN Transistor and the LED glows. Circuit Diagram: Figure 1: Automatic Night Light using Phototransistor Circuit simulation made in Multisim Figure 2: Automatic Night Light using Phototransistor

This is  Interview question that every PLC programmer came across in his carrier.The Question is very tricky and shows the fundamentals (basic Ladder Laws) and depth of candidates knowledge. Today we are going to discuss PLC program for Push to ON device  and Push to Off Device.But the trick is that we have to use  only Normally open(NO) ,Normally Close (NC) contacts ,and Coil as output only(No timer,Counter, OSR ). In short there will be a single Push Button Input (X0) , and one Output (Y0). When user press Push button for 1st time output will be ON ,when user Presses Push Button for 2nd time output will be OFF. This is also called as "Push to On Push to Off " logic.Analogy can be provided with "TV" on and off Push Button.    We Can Break Sequence Like This : 1) Push Button Pressed (X0) ==> Output (Y0)On 2)Push Button Released (X0)==> Output (Y0) Latched 3)Push Button Pressed (X0)==> Output (Y0 )Off 4)Push Button Released (X0)==> Output (Y0) O...