Power failure and resumption alarm and indicator circuit using 555 timer ic


Power failure and resumption alarm cum indicator circuit using 555 timer ic

Author: Manikandan K J

Benefits of Power failure and resumption alarm:

Power failure and resumption alarms are vital instruments that offer a multitude of advantages in many environments. The purpose of these alarms is to notify individuals or organisations in the event of a power outage and subsequent restoration of electricity. The incorporation of these warnings into various systems presents multiple benefits, which include:

1. The safeguarding of equipment: Power outages can result in adverse consequences for delicate equipment, including computers, servers, and medical apparatus. The timely notification of individuals to a power outage facilitated by these alarms enables swift response measures, such as the cessation of equipment operations or the initiation of backup power systems. This measure serves to mitigate harm and probable loss of data, so safeguarding the durability and dependability of valuable equipment.

2. Safety and Security: The occurrence of power outages can give rise to potentially dangerous circumstances, especially in locations where the functioning of emergency lighting, fire alarm systems, or security systems is contingent upon an uninterrupted power source. Power failure alarms serve the purpose of rapidly notifying individuals about any disruptions in power supply, thereby enabling them to promptly respond and take necessary measures to uphold a safe and secure workplace. The importance of this matter is particularly pronounced in environments such as healthcare institutions, industrial plants, and communal areas, where the absence of electrical power can give rise to substantial hazards.

3. The concept of business continuity highlights the potential negative consequences of power outages for enterprises, including financial losses due to unproductive periods, decreased efficiency, and missed chances for growth and advancement. By implementing power failure and resumption alarms, firms can promptly receive notifications when power supply is disrupted, allowing them to promptly execute contingency strategies and mitigate potential interruptions. Moreover, these alarms offer timely notifications upon power restoration, enabling businesses to promptly and effectively continue their operations.

4. Energy Efficiency: The inclusion of power failure and resumption alarms can serve as a valuable contribution to endeavours aimed at enhancing energy efficiency. Organisations may enhance their operational efficiency and implement energy conservation strategies by gaining valuable information into power interruptions and patterns. The utilisation of data-driven methodologies empowers firms to enhance their energy utilisation, mitigate wastage, and eventually decrease operating expenses.

5. The inclusion of power failure and resumption alerts provides a sense of tranquilly for individuals, organisations, and even entire communities. The presence of these alerts instills a sense of confidence that any possible power outages will be swiftly identified and resolved. The presence of this feeling of security enables folks to concentrate on their jobs without the persistent concern of unforeseen power interruptions.

In summary, power failure and resumption alarms are of significant importance in many contexts, providing advantages such as safeguarding equipment, ensuring safety and security, facilitating uninterrupted business operations, promoting energy efficiency, and instilling a sense of tranquilly. Through the integration of these alarm systems into various infrastructures, both individuals and organisations have the ability to effectively reduce the adverse consequences associated with power outages. This integration facilitates uninterrupted operations and serves to minimise potential hazards.

This circuit is designed to detect power failure and restoration in AC mains using only a few components. The main component of the circuit is the most popular timer IC 555, which is configured as a monostable multivibrator.
Battery, Diode D1, D2, Led L2 and resistor R2 are wired in such a way that the led L2 lights up only when power fails. When the power fails, the transistor Q1 is activated and is powered by the charge stored in the capacitor C3. Increasing the value of C3 from 1000uf to 2200 or 4500uF, increases the duration of the alarm during power failure.
Once the power resumes, green led L1 lights up and sounds an alarm for a time determined by R3 and C2. Increase or decrease the value of R3 and C2 as per your requirement. During power failure and resumption, the alarm sounds only for a certain time and switches off automatically.
The circuit works off a 9V battery and a 12v power supply. Apart from indicating the power failure and resumption, it sounds a short beep to indicate the voltage fluctuations. It can be housed in a box and installed where you want to monitor the status of mains.
Components Required:
Resistors (All 1/4W)
  • R1 – 4.7K
  • R2 – 3.3K
  • R3 – 100K
  • R4 – 2.2K
  • R5 – 4.7K
  • R6 – 10K (optional)
  • C1 – 47uF, 25V
  • C2 – 100uF, 25V
  • C3 – 1000uF, 25V
  • C4 – 0.01uF ceramic
  • C5 – 47uF, 25V
Led (3mm or 5mm)
  • L1 – Green
  • L2 – Red
  • D1, D2, D3 – In4007
  • DB1 – DB107 Bridge rectifier
  • U1 – 555
  • Q1 - BC558 (PNP)
9V Battery, Dc Buzzer, 0-12V,200mA Transformer, general purpose pcb, etc.

Improved Version

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  1. Dual Tone Power Failure And Resumption Alarm Circuit Using Timer Ic And A 9V Battery : https://www.kitszone.com/2022/07/dual-tone-power-failure-and-resumption.html

  2. i need the old version with 555 ic

    1. Old version circuit board is not available but, it can be easily assembled on a general purpose pcb. https://kjmindia.in/product/5-pieces-solderable-450-point-mini-breadboard-pcb/


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Simple Electronic Circuits: Power failure and resumption alarm and indicator circuit using 555 timer ic
Power failure and resumption alarm and indicator circuit using 555 timer ic
Power failure and resumption alarm cum indicator circuit using 555 timer ic
Simple Electronic Circuits
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