alarm-using 555 ic chip-normally closed-alarm on break
Required skills: Electrical Engineering, Electronics, Engineering, Manufacturing Design, Mechatronics
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Purpose of the project: I need an alarm to protect metal covers (which are rarely opened) they open downward or outward depending on the cabinet) Our problem is theft of components inside the cabinets and a need to set off an alarm if the cover is opened. We do not want to use reed (magnetic) switches because the cabinets are rarely opened and there is considerable vibration and heat as well as exposure to the elements. Reed switches would require too many more parts for the alarm circuits and increase cost as well as could be damaged by heat, vibration, and water intrusion. Needs of the alarm: (1) Description of operation: The alarm needs to be a normally closed circuit, which would alarm if the wire were cut. A wire loop made of insulated wire, would be intertwined with the vents in the covers. Should this be cut, the alarm would sound until the battery went dead. I don’t believe the wire gage it would use is important because of it being battery powered. (2) Component needs: (a) It is important for the alarm to use a readily available and cheap IC like a 555 IC. (b) It must have a loud alarm, 132 decibel like found in personal alarms. (c) The alarm would need to be battery powered by a physically small battery, maybe a 9 volt battery. (d) The box containing the alarm must be as small as possible and the case needs to be easily obtainable and cheap. All must fit in a plastic containment of 5 inches by 5 inches or LESS. The alarm would be mounted in an area where there are already electronics components which are protected from the weather, so the container of the IC is not subjected to the elements, but is subjected to vibration and heat up to 110-120 F. (e) The place where the wire loop attaches needs to have two terminals with metal screws or “screw-downs for “loop wire” (could be like the ones used for stereo speakers) (when wire is cut alarm will sound) I will be using possibly a gauge of wire like insulated telephone wire (#24 gauge) or slightly larger (f) This must have a “test” button button (push=on; release=off) and a way to cancel alarm by the owner. (micro-switch push=on , push=off) or tiny toggle switch (g) short alarm for low battery (h) very low battery drain while circuit is in alarm-off mode (i) The components must be cheap and easily obtainable costing no more than $ 5.00 total Our budget for this project is 300.00. These is also an extra $ 200. for detailed instructions of building this simple alarm and a source of having this alarm built in quantities of 1000 Pieces. Also, I must have complete instructions concerning construction so I may build it myself. |
Posted In:ElectronicsEngineering |
