07-03-2011, 12:30 PM
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Automatic Control of Exhaust Fan Coupled With Gas Leakage Detector
Abstract:
The term automatic control of exhaust fan is that acting in an independent manner, where the exhaust fan will work automatically in this technology. As in the kitchen were the gas leak refers to a leak of natural gas, from a pipe or other containment, into a living area or any other area where the gas should not, in such case this system will help to switch on the exhaust fan to avoid any accident.
Functional Block Diagram.
Functional description:
Here the output of the gas sensor i.e. voltage drop across is applied to the comparator with reference voltage also. If at all any gas leakage occurred then the voltage drop across the sensor is going to change, hence the change in the out put state of the comparator.
This change in the output of the comparator is detected by the microcontroller, then controller switches on buzzer to indicate the leakage and also the fan is switched ON to exhaust the gas to avoid any possible fire accident.
Mean time the system will be continuously checking the out put of the comparator, again if there is a change the fan will be switched off automatically.
Advantages:
• Safe to use and cost effective.
• Automatic ON and OFF of fan with buzzer indication
