Delay timer is a device which is used to take some duration before switch on the main input supply to any equipment . … When switch on the circuit then capacitor start charging and amount of power go to the capacitor till charge, after some seconds it get fully charged

Hello Friends, In this article, I will explain how to control AC appliances ON-OFF time using the

The simple delay timer circuit is similar and has just a few more components. So, Let’s Starts with the materials required and diagram followed by explanation and video for let’s start IC555 DELAY TIMER Control AC appliances ON-OFF time.

Off Time Delay Timer Circuit Diagram

on delay timer circuit diagram
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Parts List For Delay Timer Circuit

  • IC555-1Pcs  
  • R1-10K, R2 & R3 1k all 1/4watt 
  • VR1 470k to 1Mega 
  • D2-LED 
  • Transistor BC547/BC548 
  • C1 470uf-2200uf 25Vmax any 1 pc
  • PCB Relay – 5V To 12V according to Input Supply                                                                                       
  • Push-button-1Pcs  
  • D1 1N4007-1Pcs 
  • Battery or power supply 5V-12V 
  • PCB

The  delay timer circuit is quite simple. D1 diode 1N4007 which will be a protection to the circuit from flybacks by the relay coil and 12v relay. The delay time is decided by capacitor C1 & VR1 that has to be checked either by simulation or by testing first on a breadboard.

This design shows how the Counter Timer can be used to measure the
the pulse width of a simple 555 monostable.

The timer is set to operating in timer mode, whilst the 555 output controls its clock enable input. The count thus advances whilst the output is high.

The reset edge is set to high->low such that the timer is reset when the
the button is released.

When pin3# signal output is high the relay is turned ON and com is connected to the NO and the device is connected to the AC supply. After the time completes (capacitor discharges) the IC’s pin3# output goes off and the relay is also turned off and com again Connects to NC.

The delay time is varied by varied the changing capacitor values and adjusting the VR1 if we using 1000uf and adjusting the VR1 at 1Mega than time is around 20 min (maximum time with 1mega and 1000uf)

PCB Layout For Off Delay Timer Circuit Diagram

Delay Timer Circuit Diagram

How To Make Simple Delay Timer Circuit Watch The Video