UK diy (uk.d-i-y) For the discussion of all topics related to diy (do-it-yourself) in the UK. All levels of experience and proficency are welcome to join in to ask questions or offer solutions.

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
  #1   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 8,319
Default 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



  #2   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 74
Default 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


  #3   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 286
Default Dawn/Dusk Sensors


"The Medway Handyman" wrote in

I'm confused.



http://en.wikipedia.org/wiki/Photoresistor



  #4   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 8,319
Default 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


  #5   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 519
Default 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.
Reply
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules

Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Anyone know optical sensors Joe AutoDrill Woodworking 14 August 5th 06 05:17 PM
Sensors to connect to PC Paul Aspinall Electronics 0 October 26th 05 04:23 PM
motion sensor light stuck on dusk-to-dawn mode E Gregory Home Repair 1 June 29th 05 01:07 AM
outside lighting and dusk sensor TrueBlue UK diy 9 April 10th 05 04:36 PM
Does The 3M Woodworking Dusk Mask Irritate Your Throat? x071907 Home Repair 2 April 4th 04 07:35 PM


All times are GMT +1. The time now is 09:24 AM.

Powered by vBulletin® Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 DIYbanter.
The comments are property of their posters.
 

About Us

"It's about DIY & home improvement"