working principle:
By detecting changes in the intensity of sunlight outside the outside world, feedback to the automatic air conditioning system
Output current signal, current is small, sampling is simple

What is a daylight sensor?
Daylight Sensor is a sensing device, equivalent to a power supply box, the adjacent red stone or body power supply. When the sensor is connected to a non-door, if the light level is less than 4, a signal is output.
You can do something related to time, such as doing a night to open the day off the automatic street lights. you can also completely closed it, so he can detect the moonlight signal, and then can be away from his place to put a comparator.  In 1.8 and above, there is another way to make it a reversing sun sensor - Right-click the daylight sensor to turn it into a reverse sun sensor.

Features:
The daylight sensor only responds to the brightness caused by the sun (moonlight), and other artificial light sources (such as torches) are ineffective.
The daylight sensor is thinner than the step.
Rain will affect the sun / reverse daylight sensor.
After the glass is damaged, the items will not be dropped, but the sun sensor will contain the glass but will destroy the corresponding items.
The sun sensor can serve as a fuel for the furnace.
The daylight sensor can not be pushed by the piston.
Sun / reverse sun sensor in hell and the end of the road there is no signal output.


Daylight sensor output value:
The following table for different weather conditions under different brightness, different time under the sun sensor output signal strength, It is only suitable for daylight sensors.
When the top of the daylight sensor has a non-transparent block block, the signal strength will be weakened. This feature can be used to make street lights by combining a daylight sensor with a non-door.

Please note that although the moonlight also has 4 brightness, but only the sun can the role of the sensor, So in fact the output intensity of the night can be reduced to 0. The output of the daylight sensor is no signal at time from 13680 to 22340.



Sunny weather signal output value

Signal strength	The time to reach the brightness	The brightness cut-off time	Brightness level
0	N/A	N/A	4–5
1	22340	13680	4–7
2	22800	13220	7–9
3	23080	12940	9–11
4	23300	12720	11–12
5	23540	12480	12–13
6	23780	12240	13–14
7	23960	12040	15
8	180	11840	15
9	540	11480	15
10	940	11080	15
11	1380	10640	15
12	1880	10140	15
13	2460	9560	15
14	3180	8840	15
15	4300	7720	15

 
Rainfall weather output signal value

Signal strength	The time to reach the brightness	The brightness cut-off time	Brightness level
0	N/A	N/A	4–5
1	22340	13680	4–7
2	22800	13220	6–8
3	23240	12780	8–10
4	23520	12500	9–11
5	23760	12260	10–12
6	0	12020	11–12
7	400	11620	12
8	900	11120	12
9	1440	10580	12
10	2080	9940	12
11	2880	9140	12
12	4120	7900	12

 
Night signal output
Due to the loopholes, the covered sensor also has a signal at night. The following table corresponds to a sensor that can not receive sunlight. The weather effect does not work for the sensor at night.

Signal strength	The time to reach the brightness	The brightness cut-off time
1	14360	21660
2	14740	21280
3	15120	20900
4	15500	20520
5	15900	20120
6	16320	19700
7	16760	19260
8	17240	18780
9	17780	18240