What are the elements of photoelectric sensor selection

The discovery of electric energy brings us infinite light and unprecedented power, which directly drives our life forward at full speed.The combination of light and electricity also brings us infinite possibilities.

The working principle of photoelectric sensor is to realize the judgment of on and off through the blocking and conduction of infrared emission light and the current change induced by infrared receiving tube.Slot optocoupler is usually also called slot photoelectric switch, which is usually u-shaped structure. Its transmitter and receiver are located on both sides of the u-shaped groove and form an optical axis. When the detected object passes through the u-shaped groove and blocks the optical axis, the photoelectric switch will generate the detected switch signal.The slot photoelectric switch is safe and reliable for detecting high-speed changes and distinguishing transparent and semi-transparent objects.

What are the elements of selection of photoelectric sensor?

Structure type: amplifier separation type, amplifier hidden type, etc

(2) detection methods: reflection, regression reflection, diffusion reflection, etc

(3) working power supply: dc, ac, ac-dc general (E3JK/E3JM, E3G series)

(4) test distance: see the product sample data for details

Detection objects: shape, size, color

6 control output: transistor output, relay output, etc

7 connection: wire lead out type, plug - in - type

Today other functions: delay function, counter function and so on

(9) accessories: slit, reflector, installation accessories, etc

A, selection

There are three main considerations for the selection: how wide slot width;Resolution (light slit width);Fixed way

1, slot width, the detection of objects need to pass through the trough type optical coupler slot, to achieve the blocking of infrared light, so the photoelectric sensor slot width should be wider than the detection of objects, and there must be a certain amount of allowance, easy to install.

2, the resolution of the optical coupling slot type, such as detection is a tooth plate, the plate of tooth width is d, toothed plate of alveolar width is 3, the coupling of the light, groove width requirement is less than d, and less than f, which ensures that infrared light can be effectively blocking and conduction, to meet the above conditions, choose light split wide groove type optical coupling.

3. There are two kinds of groove type optical couplers with fixed holes and without fixed holes, which can be selected according to the actual situation.

4. Installation location.When the sensor is installed, the outer diameter of the detecting tooth disc should exceed 1-2mm of the groove photocoupler optical axis.This effectively blocks the light.

Selection of peripheral circuit parameters

1. When selecting the external circuit of the groove type optocoupler, determine the load resistance of the receiving tube of the groove type optocoupler first, and then choose the current of the infrared emitter tube according to the conversion efficiency of the groove type optocoupler.

2. The faster the movement speed of the measured object (such as 1-2khz), in principle, the value of the load resistance of the infrared receiver tube should be smaller.

Iii. Precautions for use

How to deal with the problem of photoelectric sensor in use?How can we reduce photoelectric sensor failure?This is a lot of users in the use of photoelectric sensor will encounter problems, so how to solve these problems, in fact, in daily life more attention to the use of photoelectric sensor can reduce the occurrence of the fault, the following small make up to introduce the photoelectric sensor use matters needing attention.

1. The front end of the photoelectric sensor in use must be parallel to the detected workpiece or object surface, so as to achieve the highest conversion efficiency of the photoelectric sensor.

2. When installing and welding, the minimum distance between the pin root of photoelectric sensor and the welding pad shall not be less than 5mm, otherwise the pipe core may be easily damaged during welding.Or causes the tube core performance change.Welding time should be less than 4 seconds.

3. The minimum detectable width of the optoelectronic sensor is 80% of the width of the optoelectronic switch lens.

4, when using inductive load (such as lamp, motor, etc.), its transient shock current is large, may degrade or damage the ac two-line photoelectric sensor, in this case, please transfer the load through the ac relay for use.

5, the lens of infrared photoelectric sensor can be wiped with mirror paper, prohibit the dilution of solvents and other chemicals, so as to avoid permanent damage to the plastic mirror.

6. According to the actual requirements of the user on the spot, in some harsh conditions, such as the occasion of more dust, the sensitivity of the photoelectric sensor produced increased by 50%, so as to meet the requirements of extending the maintenance period of the photoelectric sensor in long-term use.

7, photoelectric sensor must be installed in no direct exposure to strong light, because the infrared light in the strong light will affect the normal work of the receiving tube.