Inductive sensors Manufacturers online

Inductive sensors are non-contact proximity sensors based on the principle of electromagnetic induction.

They use magnetic fields to detect metal objects. They are often used in automation technology, the manufacturing industry and other applications.

Below you will find how inductive sensors work, the typical designs, their areas of application and their advantages and disadvantages:

How it works:

An inductive sensor generates an alternating electromagnetic field that is produced by an oscillator. If a metal object is in the vicinity, it causes a change in the magnetic field, which leads to an attenuation effect in the oscillation circuit.
As soon as the attenuation reaches a threshold value, the sensor switches a signal to indicate the presence of a metallic object.

Typical designs:

• Cylindrical sensors have a round design and are often offered in standard sizes such as M8, M12, M18 or M30.
• Flat cuboid sensors are suitable for special mounting requirements, for example where space is limited.

Typical areas of application:

1. Position detection:
Inductive sensors are used to detect the position of metallic components in machines. For example in conveyor belts, CNC machines or robot arms.

2. Counting tasks:
They can be used to count metal parts passing a certain point. This is useful in production lines to check that all parts are being transported correctly.

3. Speed detection:
In rotating machinery, inductive sensors can be used to detect the number of revolutions of metal gears.

4. End position monitoring:
In hydraulic systems or pneumatic cylinders, inductive sensors can be used to check whether a cylinder has reached its end position.

Advantages of inductive sensors:

• As the sensor does not require direct physical contact, there is no mechanical wear.
• Inductive sensors can perform very fast switching operations, which makes them suitable for dynamic applications.
• They are resistant to dirt, oil, dust and water, making them ideal for harsh industrial environments.

Their disadvantages:

• Inductive sensors have a relatively short sensing range (usually between 1 and 10 mm), which limits their use to close-range applications.
• These sensors only work with metallic materials, which limits their use to certain applications.

Inductive sensors are a reliable, cost-effective solution for non-contact detection of metal objects and play a crucial role in automation technology. They are particularly useful in applications where robustness and precision are required but only metallic objects need to be detected.

Below you will find an overview of the most important criteria to look out for when purchasing inductive sensors:

When purchasing inductive sensors, there are several important factors that should be considered to ensure that the sensor is suitable for the application in question.

• The nominal switching distance indicates how far the sensor can detect an object. Depending on the model, this value is typically between 1 mm and 20 mm.
• In practice, the detection range is often somewhat lower than the nominal value, as the material and size of the target object can have an influence. Metallic objects made of iron often result in a maximum detection range, while other metals such as aluminum or copper result in a lower range.
• Choose a sensor with sufficient range for your application. A safety factor of 1.5 to 2 times the nominal detection range can be useful to ensure reliable detection.
• Commonly used cylindrical designs are M8, M12, M18 and M30. The size often influences the detection range (larger sensors often have a longer range).
• Cuboid flat sensors are suitable for confined installation situations or when mounting on non-cylindrical surfaces is required.
• Pay attention to the space available at the mounting position and choose a design that is easy to install and fits perfectly into your system.
• Metal enclosures are more robust and resistant to mechanical stress, ideal for harsh environments.
• Plastic enclosures are lighter and more resistant to corrosion, making them more suitable for chemical or humid environments.
• Select the enclosure material according to the environmental conditions (humidity, chemicals, mechanical stress).
• Select the switching type according to the required logic of your control system or machine control.
• Normally open (NO): The sensor gives a signal when an object is detected.
• Normally closed (NC): The sensor emits a signal when no object is detected.
• Changeover switch (NO+NC): Both present in one sensor.
• Check which voltage is available in your system and select the sensor accordingly.
• DC sensors (direct voltage): Typically operate at 10-30 V DC.
• AC sensors (alternating voltage): Often operate in the range of 20-250 V AC.
• Multi-voltage devices: Some sensors support both AC and DC.
• Ensure a sufficient protection class, especially if the sensor is used in harsh environments with dust, moisture or chemicals.
• IP67: Protected against the ingress of dust and against temporary immersion in water.
• IP68: Provides protection against permanent immersion in water.
• Check the ambient temperatures in your installation and select a sensor that meets the requirements.
• Inductive sensors typically operate at temperatures between -25 °C and +70 °C. Special versions can support a wider temperature range (e.g. down to -40 °C or +100 °C).
• Check the ambient temperatures in your system and select a sensor that meets the requirements.
• Select the appropriate connection option depending on the application requirements. Connectors usually offer more flexibility and easier maintenance.
• Permanently installed cable for the electrical connection.
• Plug-in connectors (e.g. M8 or M12) are the more flexible solution, as the sensor can be easily replaced if necessary without having to re-route the entire cabling.
• Select the switching frequency according to the speed of the object or machine.
• Inductive sensors have a high switching frequency and can achieve several thousand switching cycles per second. This is particularly important for fast-moving objects.
• In environments with strong electrical interference fields, sensors with high EMC resistance should be used.
• Inductive sensors are generally insensitive to electrical and magnetic interference that can be caused by motors or other electrical devices. Nevertheless, care should be taken to ensure that the sensor has sufficient electromagnetic compatibility (EMC).
• Do not necessarily buy the cheapest sensor, but look for a model that reliably meets your requirements and has a long service life.

When purchasing an inductive sensor, you should ensure that the specifications match your application. The most important factors are the detection range, the design, the housing material, the supply voltage and the environmental influences such as temperature and protection class. A sensor that meets these requirements offers reliable performance and a long service life.

Inductive sensors can be purchased from various suppliers. Comprehensive information about manufacturers and suppliers of Inductive sensors from all over the world can be found on Exportpages.