The automatic globe light control circuit is a simple and effective solution to control the operation of globe lights. It automatically turns off the light after a predetermined amount of time when someone turns it on. This circuit is designed to address the issue of wastage of electricity that occurs when globe lights are inadvertently left on. By implementing this circuit, energy can be conserved and costs can be reduced.
The circuit diagram above shows the configuration of the globe light control circuit. It consists of two transistors, resistors, capacitors, and a switch. The primary purpose of this circuit is to introduce a delay and automatically turn off the light after a specific period of time.
The following components are required for building the globe light control circuit:
- R1: 10k Ohm
- R2: 150k Ohm
- R3: 120 Ohm
- R4: 100k Ohm
- C1: 220uF
- C2: 10nF
- Q1: BC547 (NPN)
- Q2: BC557 (PNP)
- BAT1: 6V Battery
- GLOBE: 6V Globe Light
When the switch button is pressed, the NPN transistor BC547 turns on due to the forward biasing voltage from the base to the emitter. At the same time, capacitor C1 starts charging through the 6V battery. Transistor Q1 is turned on and the PNP transistor Q2 is also activated through the collector output of transistor Q1.
Even after the push button is released, the globe light remains turned on due to the charge stored in capacitor C1. The light will remain on until the capacitor is fully discharged. By adjusting the value of the capacitor, the turn-on time can be increased or decreased according to the desired requirement.
The automatic globe light control circuit finds applications in both residential and industrial settings. Some of the notable applications include:
- Homes: It is a useful solution in homes to automatically turn off globe lights in areas such as corridors, toilets, or rooms where people often forget to switch off the lights.
- Offices: In office buildings, this circuit can be employed to control the lighting in common areas like hallways, parking lots, and conference rooms. It ensures that lights are not left on unnecessarily, leading to energy savings.
- Public Areas: The circuit can also be implemented in public areas such as libraries, museums, and shopping centers, where lights need to be operational for a limited period when no one is present.
By utilizing the automatic globe light control circuit, electricity wastage can be minimized, contributing to a more energy-efficient and sustainable environment.