Light Switch | Electronic Project Circuits

Posts Tagged ‘light switch’

Simple Light Actuated Relay by Phototransistor

The Sun – Up Relay Switch can be used to provide a audible switch for when the sun comes up. It can also be used to detect a light beam, headlights etc.
This circuit is easy because it used one Transistor 2N2222-2SC945-2SC828-BC549 etc , Relay and Photo transistor Only. The important part of the circuit is very low cost. (I like it)
The photo transistor is very sensitive to light. VR1 for control sensitive of circuit.
Relay used 6V to 9V 600ohm.

Be the first to comment - What do you think? Posted by admin - May 1, 2008 at 8:42 am

Categories: Detector, Lighting Tags: light switch, lighting senser, phototransistor circuits

Automatic Lamp Control with Light Sensitive Switch

The circuit above is an automatic switch which functions in absence of light. The IC 4060 works as an oscillator and the generated signal is applied to the base of T4 transistor. Phototransistor T3 is in conduction by existance of light and it keeps the T5 transistor’s base at ground potential.
When no light reachs the phototransistor, it gets in insulation. T3 reachs positive potential through 22kohm. T4 and T5 both gets in conductance. The oscillator signal reachs the optic coupler and lamp(s) shines.

Source: http://www.circuit-projects.com/automatic-lamp-control-withlight-sensitive-switch.html
Thank you.

Be the first to comment - What do you think? Posted by admin - February 7, 2008 at 10:16 am

Categories: Electronic Control, Lighting Tags: Electronic Control, IC 4060, light switch, lighting senser

LED4 LED Sensor Electronic Tracker with Simple Solar Charge Controller.

The “LED3″ light sensor works very well. It is sensitive, accurate, and cheap. A couple of years ago I had devised a simple solar charge controller I called “Shunt 2″. I thought it would be a good idea to combine them into a single PC board called the LED4.

Note! I no longer sell the LED4 as it was replaced by the much more capable LED3X. Ok, the LED3X doesn’t have a charge controller but this isn’t really required to run the tracker.

The design philosophy for this tracker was to make it more robust and self contained. I included a charge controller for rechargeable batteries intending them to be NiCds to run the actuators. Since the charger is there it might as well be capable of running a large PV panel with lead acid batteries.

Note! this charger is not intended to charge the expensive system batteries. Leave that job to the high end smart charger such as those by Trace, Outback, and others.

It can also run a very small PV panel to charge the local NiCds or NiMH batteries. These batteries work well over a wide temperature range.

I will test the ability of the sensors to be at the end of a long cable. I will test this using 1000′ of 4 wire telephone cable. 8 wire Cat5 cable should also work with the extra wires driving the actuators.

With the use of long Cat5 cable the main board can be inside a heated battery room. Of course you still have to run the heavy gauge main charging wire pair to the battery room. The advantage of having the batteries in a heated room is temperature compensation won’t be needed.

Read More Source: http://www.redrok.com/electron.htm#led3x Thank you.