Cause analysis of no output signal of photoelectric sensor

The photoelectric sensor has the characteristics of high precision, fast response, non-contact measurement and simple structure, and it is widely used in detection and control. Although the form of photoelectric sensors is flexible and diverse, there are generally some technical problems that need to be further eliminated.

When many users detect objects, the sensor does not display a signal. Most people often think that the photoelectric sensor is broken, but this is not the case. Let's analyze it for everyone below.

The first thing to consider is the problem of wiring or configuration. For the through-beam type photoelectric sensor, it must be used in combination with the light-emitting part and the light-receiving part, and both ends need to be powered; while the retro-reflective type must be used in combination with the sensor probe and the retro-reflective plate; at the same time, the user must provide stable power to the sensor, if For DC power supply, the positive and negative poles must be confirmed. If the positive and negative poles are connected incorrectly, the output signal will be missing.

The above reason analysis is the consideration of the photoelectric sensor itself. What we also need to consider is the position of the detected object. If the detected object is not in the detection area, such detection is futile. The detection object must be within the area that the sensor can detect, that is, within the range that the photoelectric can detect. Secondly, it is necessary to consider whether the optical axis of the sensor is aligned. The optical axis of the through-beam type projecting part and the light receiving part must be aligned, and the corresponding retro-reflective probe part and the optical axis of the reflector must be aligned. The same thing to consider is whether the detection object meets the standard detection object or the minimum detection object standard. The detection object cannot be smaller than the minimum detection object standard, so as to avoid causing the through-beam type and the reflection type to not be able to detect transparent objects well, like the reflection type. The color of the detected object is required. The darker the color, the closer the detection distance. If the above conditions are eliminated, the next thing to do is to check the interference of environmental factors.

For example, the light intensity cannot exceed the rated range; if there is dust in the field environment, we need to clean the surface of the photoelectric sensor probe regularly; or multiple sensors are installed tightly and interfere with each other; there is also electrical interference. For high-power equipment, corresponding anti-interference measures must be taken when interference occurs. If you have done the above-mentioned investigations one by one, and these factors can be clearly eliminated or there is no signal output, it is recommended to return to the manufacturer for inspection and judgment.