Dawn/Dusk Sensors
Hi All
Had a job today, lady recently moved in, hall light had packed up. Turned out to be a faulty dawn to dusk sensor. White plastic thingy about 80mm long, 30mm dia with a male bayonet one & a female the other. Removed it, Robert is your fathers brother. Got me thinking though! How do these things work? I can see the logic of 'it's dark, switch on' but how do they stay on? I assume they have a photo cell of some kind? Why doesn't the light coming from the bulb trigger the sensor and turn the bulb off? Daylight would trigger it and the bulb is much closer & brighter. I'm confused. -- Dave The Medway Handyman www.medwayhandyman.co.uk 01634 717930 07850 597257 |
Dawn/Dusk Sensors
"The Medway Handyman" wrote in message . uk... Hi All Had a job today, lady recently moved in, hall light had packed up. Turned out to be a faulty dawn to dusk sensor. White plastic thingy about 80mm long, 30mm dia with a male bayonet one & a female the other. Removed it, Robert is your fathers brother. Got me thinking though! How do these things work? I can see the logic of 'it's dark, switch on' but how do they stay on? I assume they have a photo cell of some kind? Why doesn't the light coming from the bulb trigger the sensor and turn the bulb off? Daylight would trigger it and the bulb is much closer & brighter. I'm confused. -- Dave The Medway Handyman I suspect its down to frequencies of light; natural light must produce a certain frequency of light the bulb does not produce, and when the sensor detects it, it turns the light off cus it knows it must be day time. Steve |
Dawn/Dusk Sensors
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Dawn/Dusk Sensors
George wrote:
"The Medway Handyman" wrote in I'm confused. http://en.wikipedia.org/wiki/Photoresistor I'm slightly more confused now :-) Are you/wilkapedia saying it the frequency of the light that triggers the sensor, What would happen with a 'daylight' bulb? -- Dave The Medway Handyman www.medwayhandyman.co.uk 01634 717930 07850 597257 |
Dawn/Dusk Sensors
The Medway Handyman wrote:
Hi All Had a job today, lady recently moved in, hall light had packed up. Turned out to be a faulty dawn to dusk sensor. White plastic thingy about 80mm long, 30mm dia with a male bayonet one & a female the other. Removed it, Robert is your fathers brother. Got me thinking though! How do these things work? I can see the logic of 'it's dark, switch on' but how do they stay on? I assume they have a photo cell of some kind? Why doesn't the light coming from the bulb trigger the sensor and turn the bulb off? Daylight would trigger it and the bulb is much closer & brighter. They turn off for .5 sec every half an hour or so, to see if it's still dark. |
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