Inductive sensor how does it work

Power Drain: The amount of current required to operate a sensor. Voltage Drop: The voltage drop across a sensor when driving the maximum load. Short Circuit Protection: Protection against damage to a sensor if the load becomes shorted.

According to EN , this parameter is measured by the dynamic method shown in fig. S is the operating distance and m is the diameter of the sensor. The frequency is given by the formula in fig. This distance reduces false triggering. Its value is given as a percent of the operating distance or a distance. See Fig. Flush Mounting: For side by side mounting of flush mount models refer to Fig.

Non-flush mount models can be embedded in metal according to Fig. Protection against water jets. IP Dust tight. Protection against the effects of immersion. Click here for full product details and info on other special offers.

All Rights Reserved. Table 1. Sensitivity when different metals are present. The bulk of material and the requirement for carefully wound coils makes them expensive to produce, especially high accuracy devices that require precision winding.

Besides simple proximity sensors, the more sophisticated inductive sensors are prohibitively expensive for many mainstream, commercial or industrial applications.

Another reason for the relative scarcity of inductive sensors is that they can be difficult for a design engineer to specify. This is because each sensor often requires the associated AC generation and signal processing circuitry to be separately specified and purchased.

This often requires a significant amount of skill and knowledge of analogue electronics. Next generation devices However, a new generation of inductive sensor has entered the market in recent years and has a growing reputation, not only in the traditional markets, but also in industrial, automotive, medical, utility, scientific, oil and gas sectors.

This new generation of inductive sensor uses the same basic physics as the traditional devices but uses printed circuit boards and modern digital electronics rather than the bulky transformer constructions and analogue electronics. The use of printed circuits enables sensors to be printed onto thin flexible substrates, which can also eradicate the need for traditional cables and connectors.

The flexibility of this approach — both physically and from the ability to readily provide customised designs for OEMs — is a major advantage of this new approach. As with traditional inductive techniques, the approach offers reliable and precision measurement in harsh environments. There are also some important advantages:.

Zettlex designs and manufactures sensors; supplies sensor components and integrated circuits. The company offers bespoke sensor design and development for specific customer applications. By Mark Howard, Zettlex Inductive sensor terminology and techniques can be confusing. This article explains the various types and operating principles, as well as their consequent strengths and weaknesses. We will explain what an inductive sensor is, how an inductive sensor works, some of the different types of inductive sensors, and we will also talk about some of the ways these sensors are used in automation.

An inductive sensor is an electronic device that can detect ferrous metal targets without physical contact. Inductive sensors will also detect non-ferrous metal targets like aluminum, brass, and copper. The datasheet will also show some correction factors when you want to detect a non-ferrous metal. Non-ferrous metal is a type of metal that does not have a significant amount of iron in it. Brass, aluminum, and copper are examples of non-ferrous metals.

This means these metals do not have a significant amount of iron within them. Here for this inductive sensor, the datasheet shows the sensing distance as 12 mm. This works only when the object is steel which has a significant amount of iron in it.

If the object is a non-ferrous metal, meaning it does not have a significant amount of iron within it, you need to consider a simple correction factor when defining the sensing distance. For example, here it says if the object is made of brass , you simply need to multiply the normal sensing distance for the sensor by 0.

So, if we multiply 12 mm by 0. This means if we want to sense an object that is made of brass, the distance between the sensor and the object should not be more than 6 mm for this sensor to be able to sense the object.

The same goes for other non-ferrous metals as well. For example, if we have an object that is made of aluminum , the sensing distance for this inductive sensor is 12 mm multiplied by 0. This gives us a sensing distance of 4. For a copper object, the sensing distance will be 12 mm multiplied by 0. As you can see, here it shows the correction factor for steel as 1.

Steel is a ferrous metal as it has a significant amount of iron in it. So, the sensing distance for an object that is made out of steel is 12 mm multiplied by 1 which is equal to 12 mm.

The indicator light is usually near where the cable gets connected to the sensor. The indicator light turns on when the target is within the sensors sensing range. These sensors are available with a cable that is already attached or they can have a connector that the cable screws on to.

This makes them very reliable because they usually only need to be replaced when they get physically damaged. Inductive sensors can get dirty and still work.