Hello all,
My uncle, a Midwest farmer, has been attempting to construct a basic system for use on a farming implement after failing to find something similar he could purchase. He acquired all of the individual components and then contacted me when they failed to perform as expected. Unfortunately I am a mechanical engineer and have very little experience with this type of electronics.
His Proposal:
A visual and audible safety warning system powered by a tractors 12VDC supply. The circuit is activated/deactivated via a NO magnetic reed switch. When the switch is closed, 8 LEDs and a buzzer are energized and remain so until the magnets proximity to the switch surpasses its operating distance. The circuit also contains a rocker switch enabling the system to be manually deactivated regardless of the condition of the reed switch.
He previously purchased standard LEDs and was attempting to make them flash when activated. I suggested he simply acquire flashing LEDs to simplify the design, which he has done. If this was an uneducated suggestion, please let me know.
My (His) Request:
Conversations with him seem to indicate that he was most likely able to assemble a fully working design with the exception of the LEDs. He said he was able to get one LED with a resistor to function, but not at the required 12 volts. At full voltage, he said the LED would switch from a flashing state to on but no longer flashing. The LEDs are 3.5V/20mA and the alarm is 12VDC 18mA(max.). I unfortunately could offer him very few suggestions but told him I would find someone who could. Given that this will function as a safety device, I would very much like to see it work for him.
I have attached a very rough Visio generated drawing representing all known components organized in the way he wants his final design to appear. If any portion of this layout is unclear, I will be happy to provide clarification. I would very much appreciate any direction I could offer him based on your suggestions. Any visual aids that would prevent translation errors between me and him would most likely be very helpful.
Thank you in advance for any and all instruction offered.
My uncle, a Midwest farmer, has been attempting to construct a basic system for use on a farming implement after failing to find something similar he could purchase. He acquired all of the individual components and then contacted me when they failed to perform as expected. Unfortunately I am a mechanical engineer and have very little experience with this type of electronics.
His Proposal:
A visual and audible safety warning system powered by a tractors 12VDC supply. The circuit is activated/deactivated via a NO magnetic reed switch. When the switch is closed, 8 LEDs and a buzzer are energized and remain so until the magnets proximity to the switch surpasses its operating distance. The circuit also contains a rocker switch enabling the system to be manually deactivated regardless of the condition of the reed switch.
He previously purchased standard LEDs and was attempting to make them flash when activated. I suggested he simply acquire flashing LEDs to simplify the design, which he has done. If this was an uneducated suggestion, please let me know.
My (His) Request:
Conversations with him seem to indicate that he was most likely able to assemble a fully working design with the exception of the LEDs. He said he was able to get one LED with a resistor to function, but not at the required 12 volts. At full voltage, he said the LED would switch from a flashing state to on but no longer flashing. The LEDs are 3.5V/20mA and the alarm is 12VDC 18mA(max.). I unfortunately could offer him very few suggestions but told him I would find someone who could. Given that this will function as a safety device, I would very much like to see it work for him.
I have attached a very rough Visio generated drawing representing all known components organized in the way he wants his final design to appear. If any portion of this layout is unclear, I will be happy to provide clarification. I would very much appreciate any direction I could offer him based on your suggestions. Any visual aids that would prevent translation errors between me and him would most likely be very helpful.
Thank you in advance for any and all instruction offered.
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