Introdução
When using photo control devices (also known as light controllers) in everyday applications, users sometimes complain about a “clicking” sound after the device is turned on. There can be several reasons behind this clicking noise. In this article we will explore some of the common reasons behind this problem and how it can be resolved. So, let’s get started.
Causes of the Clicking Noise
Relay Activation Sound (Normal Phenomenon)
In some photocell models, the switching on and off of the circuits is controlled by relays. Whenever these relays are activated and released physically, they produce a clicking sound. This is something perfectly normal and should not be worrisome as it does not point to a fault in the photocell. But how would you know if the sound is a result of relay activation?
Diagnosis Criteria:
If the sound occurs regularly, such as whenever the light switches on or off, and the photocell keeps operating normally without any malfunction, you should not worry about the noise. This sound is simply the usual operation of the relay, and you should ignore it.
Internal Component Failure
Contact Oxidation/Wear
Another common reason for the clicking noise can be the internal wear and corrosion of relay components, especially when the photocell is being used for a long time, or under moist and rough conditions. The degradation of relay components can cause an occasional clicking noise.
Capacitor or Inductor Vibration
The clicking sound might also be a result of loose capacitors and inductors. This can lead to vibration whenever the device is turned on.
Diagnosis Criteria:
If the abnormal noise is followed by a malfunction, such as flickering lights or unstable operation of the light sensor, it can be a result of internal component failure. In such cases, you may need to either repair the faulty parts or get them replaced.
Power Supply or Load Issues
Unstable Voltage
Fluctuating input voltage, especially when the voltage is below the photocontrol’s rated value, can lead to repeated activation and release of the relay, producing the unusual sound. This is among some of the most commonly reported causes of the sound in photocells.
Overload
In some cases, when there is more load on the devices than their capacity, the device turns off automatically and shuts down operation with a noise. This is to ensure that the device is protected against damage caused by overload. This happens in the wake of unstable voltage.
Solutions:
You can check the input voltage by leveraging a multimeter. It can help you diagnose of the fluctuations in voltage are the reason for the tripping sound in the photocell. Make sure that the load is within the range of rated voltage for the photoelectric cell and there is no problem of overload or fluctuations.
Installation or Environmental Factors
Sometimes, improper installation or harsh environmental conditions may also cause a photocell to operate abnormally and produce unusual sounds. Below are some of the factors to watch out for.
Loose Enclosure
When the enclosure or other photocell fittings are not secured tightly, it leads to multiplying even the minor internal vibrations and you hear a sound every now and then. Tightening the screws and fixing the loose fitting components often rids you of this problem.
Moisture or Corrosion
When the photocontrol cells are being used in a moist environment, the internal circuit may get corroded due to excess moisture. This may lead to electric discharge and even short circuits. Under such cases, you may hear sounds. If this is the reason, we suggest you to repair the damaged components or replace them with new ones. Below are some other measures to take in such circumstances.
Solutions:
Ensure that the photocell is installed in a dry, well-ventilated area to avoid exposing the sensitive parts to moisture.
Regularly check the device’s enclosure and tighten any loose screws to reduce the impact of external vibrations.
LUX Threshold Overlap
The dusk-to-dawn photocells work by detecting the changing levels of ambient light. When the level of light reaches a preset threshold, the photocell lighting sensor device automatically switches the circuit on or off. If the difference between the “on” threshold (e.g., 50 LUX) and the “off” threshold (e.g., 55 LUX) is too small (less than 10 LUX), the device may frequently switch states when the ambient light is near the threshold (e.g., during dusk or dawn). As a result, the relay if abruptly engaged and released. In such cases, you may hear repeated sounds.
Solution:
Adjust the LUX threshold difference to ensure there is a sufficient gap between the “on” and “off” thresholds. The relay will hence not be activated repeatedly or very frequently and the noise will automatically subside.
Conclusão
The “clicking” noise heard after powering on a photocell switch device can be caused by various factors, ranging from normal relay operation to internal component failures, power supply or load issues, installation problems, and environmental influences. To ensure that your photocell sensor device operates smoothly and quietly, we recommend regular checks of the device, confirming stable voltage, matching load power, secure installation, and maintaining good environmental conditions.
If you encounter issues that cannot be resolved on your own, please feel free to contact us for more professional technical support and solutions. You can reach us at Zhejiang Lead Top Electrical Co., Ltd. via email: info@leaditop.com.
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