Photoresistor

[jabal29]

..I bought solar bulbs from Ali Express and I want automatic turn on and off according to ambient light..So I bought photo resistors to hook on the bulb system..There is a switch on the bulb to turn the light on with several sequences of lighting..How should I bypass that switch so to have the photo resistor control the light on and off..?

 

[Externet]

You bought the wrong light bulbs. To modify a device, you must learn exactly how was it designed. Do you have a schematic ? Are you aware if there is a microcontroller with firmware/program in it ?

 

[jabal29]

I don't know too much about electronics.. however I think it should not be very difficult to get the photoresistor operating..I thought you could tell me if I should plug it on the battery+ or -..or on the LEDs..

 

[Nigel Goodwin]

I don't know too much about electronics.. however I think it should not be very difficult to get the photoresistor operating..I thought you could tell me if I should plug it on the battery+ or -..or on the LEDs..

You think wrongly - a photo-resistor isn't a switch, you would need to add a fair few more components (such as a comparator and associated components) to make it operate as one.

 

[danadak]

Some circuits here to detect and switch on LEDs, attached


Regards, Dana.

 

[Athosworld]

You think wrongly - a photo-resistor isn't a switch, you would need to add a fair few more components (such as a comparator and associated components) to make it operate as one.

True, it changes resistance when exposed to light. To get it working you probably need a transistor and some other components like in this schematic.

 

[ZipZapOuch]

Athosworld , where did you find that terrible circuit?
I'm not sure Q1 will ever turn off with its base connected to 9v. And, why would you do high-side switching with an NPN transistor?

 

[Nigel Goodwin]

True, it changes resistance when exposed to light. To get it working you probably need a transistor and some other components like in this schematic.View attachment 143163

Worst possible 'circuit' in the world, and then it's even drawn completely wrong with parts missing

And where do you found a 100 ohm LDR?.

 

[audioguru]

Years ago, solar garden lights used photo-resistors that got sunburned and failed. New solar garden lights use the glass-covered solar panel to detect light and turn the LED on and off.