TIME DELAY BASED RELAY OPERATED LOAD SUBMITTED BY EDGEFX TEAM

ABSTRACT A circuit is designed to operate a load after a certain delay. A time delay is a relay that stays on for a certain amount of time once activated. This time delay relay is made up of a simple adjustable timer circuit which controls the actual relay The time is adjustable from 0 to about 200 seconds but can be increased by increasing the time constant of the mono-stable formed out of 555 timer

BLOCK DIAGRAM

HARD WARE EQUIPMENTS LED PUSHBUTTONS RESISTOR CAPACITOR 555 TIMER BC547 RELAY BATTERY

EMBEDDED SYSTEMS Definition for :- EMBEDDED SYSTEMS A combination of hardware and software which together form a component of a larger machine. An example of an embedded system is a microprocessor that controls an automobile engine. An embedded system is designed to run on its own without human intervention, and may be required to respond to events in real time.

EMBEDDED SYSTEMS

LED LEDs are semiconductor devices are made out of silicon When current passes through the LED, it emits photons as a byproduct. Normal light bulbs produce light by heating a metal filament until its white hot LEDs present many advantages over traditional light sources including lower energy consumption, longer lifetime, improved robustness, smaller size and faster switching

BC547 The BC547 transistor is an NPN Epitaxial Silicon Transistor. The BC547 transistor is a general-purpose transistor in small plastic packages. It is used in general-purpose switching and amplification BC847/BC547 series 45 V, 100 mA NPN general-purpose transistors. Whenever base is high, then current starts flowing through base and emitter and after that only current will pass from collector to emitter  

555 TIMER The 555 Timer IC is an integrated circuit (chip) implementing a variety of timer and multivibrator applications. The original name was the SE555 (metal can)/NE555 (plastic DIP) and the part was described as "The IC Time Machine". Depending on the manufacturer, the standard 555 package includes over 20 transistors, 2 diodes and 15 resistorson a silicon chip installed in an 8-pin mini dual-in-line package (DIP-8)

PIN DIAGRAM OF 555 The 555 timer IC is a simple 8 pin DIL package IC. It can: be used as a monostable be used as an astable source or sink 100mA use supply voltages of 5v to 15v disrupt the power supply - use a decoupling capacitor!

BATTERY An electrical battery is a combination of one or more electrochemical cells, used to convert stored chemical energy into electrical energy. The battery has become a common power source for many household, robotics and industrial applications. Larger batteries provide standby power for telephone exchanges or computer data centers

RELAY IT IS A ELECTRO MAGNETIC SWITCH USED TO CONTROL THE ELECTRICAL DEVICES COPPER CORE MAGNETIC FLUX PLAYS MAIN ROLE HERE

BIBILOGRAPHY www.beyondlogic.org www.wikipedia.org www.howstuffworks.com www.alldatasheets.com

THANK ‘Q’