Why do mercury street lights turn on automatically when it gets dark?

Intelligent street lamp through the adjustment of the output voltage of the lighting line, reduce the effective current of the light source, in the initial stage of the linear decline of the voltage, the illuminance is not significantly reduced, and the power saving is reduced by the square of the voltage.

Intelligent street lamps have the characteristics of high luminous efficiency, low power consumption, long service life, safety and reliability, strong light output of light source, and environmental protection. It is used in urban main roads, urban secondary roads, industrial park roads, urban and rural roads and other fields.

The energy-saving device of the intelligent street lamp adopts the time-sharing shift method, which takes into account the energy-saving effect of the trough period of electricity consumption under the condition of ensuring lighting. Experiments show that the intelligent energy-saving control system can significantly improve the power efficiency of street lamps and prolong the service life of street lamps. Under the premise of saving energy and rational use of power resources, the device has a very broad social and commercial prospects.

So why does the mercury street light automatically turn on when it gets dark?

In fact, the mystery lies not in the mercury street lamp itself, but in the switch of the street lamp.

Cadmium sulfide (CDS) has the property that it becomes less resistive when exposed to light. High-purity cadmium sulfide is a good semiconductor, suitable for the manufacture of devices such as light pipes. People have even applied the properties of cadmium sulfide to the ** table.

This cadmium sulfide is used in street lamps. During the day, the resistance of cadmium sulfide becomes smaller, and a large current can be passed, and the high current can make the electromagnet work, so it can automatically cut off the street light switch.

As soon as it gets dark, the current of the electromagnet is cut off, and the street light can automatically turn on the street light switch. This is called photosensitivity, and people call the detector that turns the circuit on and off by light sensitivity.

Recently, great progress has been made in the research of semiconductors and circuits, and optical sensor switches with small size and good performance are being widely used.

If this mercury lamp is used for household door lights, it can save a lot of electricity.

This is based on the photoelectric effect, from the light shining on a sensing board, the photoelectric effect occurs, generating a small current, amplifying it with an amplifier, and installing an electromagnet. Then as soon as the light is dim, the electromagnet does not attract, and then the light comes on.

This is based on the photoelectric effect, from the presence of light to a sensing board.

A photoelectric effect occurs, which generates a fine electric current, which is amplified with an amplifier.

As long as the light is dim, the electromagnet does not attract, and then the light comes on.

This is probably a sensing function.

This is probably a photoelectric effect.

Because that's how mercury street lights work.

It may be by induction, or it may be artificial.

The working principle of mercury street lamps is not very clear, after all, it has long been eliminated.

I really haven't heard of mercury street lamps.