Street Lights when referring to traffic lights flash at night when there's very little traffic.
You can still go through the street light when it's red at night but you must still watch for traffic.
If you mean the street lights that light up the street at night then the street light blinking can be caused by electrical interference or a bad light fixture or bad photocell.
LDR in street lamps works by changing its resistance when different amounts of light fall on it.
The LDR in a street lamp is a light dependent resistor and it works on the principle of photo conductivity where it gives less resistance in high light intensity and high resistance in low light intensity.
Streetlights have potential divider circuits that cause the light to come on automatically at nightfall.
When it is dark, the resistance of the light-dependent resistor (LDR) (R 2) is high, which means that the output voltage is high and can be used to switch on the light.
Street lights sometimes turn off at night because they have a timer to shut them off at a certain time such as midnight to conserve electricity.
Street lights in some places such as the UK get turned off at night to conserve energy and save money.
However in most other places such as the USA the street lights stay on all night and then turn off during the daylight hours.
The street lights turn off in Basingstoke at 1:00 AM and stay off until 4:00 AM.
The street lights in Horsham turn off at around midnight and then turn back on around 5:00 AM and stays on until daylight.
The street lights turn off in the UK by midnight and then turn back on by 5:00 AM and then stay on until daylight.
Street Lights do turn off at night in the UK after a set amount of time.
In the UK the street lights operate on GMT all year and are programmed to come on from dusk until around midnight (GMT) and then back on again from around 5.30am (GMT) until dawn - if it is still dark.
In summer time the lights still operate on GMT so will go off at around 1am (BST) and back on again at 6.30am (BST).
The street lights turn off at night in the UK to save money and energy and then they turn back on for awhile before daylight.
Street Lights typically stay on all night until the following day when they automatically turn off.
However in some places such as the UK the street lights turn off to save energy and electricity.
A street light turns on automatically by way of a photocell switch also known as a dusk to dawn switch.
The dusk to dawn switch or sensor senses the darkness which then activates the switch to complete the circuit to allow the street light to come on.
Street lights that light up the streets at night are on sensors.
Traffic lights on the other hand are on timers as well as sensors that tell the lights when to change colors.
The street lights however just turn on at night and off during the daylight hours through use of a a light sensor.
Dusk to Dawn light switches detect natural light and turn on the lights after sunset.
They also shut everything down when the sun rises, so nothing burns power during the day.
Many photocell fixtures come with motion detectors as well.
Dusk to dawn light sensors, also known as twilight switches are practical, because they automatically turn on the light with the dawn.
As soon as it gets lighter again in the morning, the light switches off again.
So the lighting is controlled based on the actual lighting conditions, regardless of the time of day.
A common reason why dusk to dawn light stays on all the time is because of system override.
This can be caused by power outages as well as small issues in your system.
Moreover, system override can occur if wires are incorrectly placed.
The good thing is that system override is easy to fix.
Some dusk to dawn lights use a photocell as a source of their power.
Photocell technology is used to identify when dusk has fallen, which prompts the lights to turn on.
Similarly, these lights detect natural light and turn off when morning comes.
Photocell lights are activated by the changing of natural light, which means that they automatically shift with daylight changes and adjust when the nights are longer or shorter.
Some photocell outdoor lights also contain motion sensors too.