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Inductive sensors use currents induced by magnetic fields to detect nearby metal objects. If there is a metal object near the changing magnetic field, current will flow in the object. This resulting current flow sets up a new magnetic field that opposes the original magnetic field.
What do inductive sensors detect?
Inductive Proximity Sensors detect magnetic loss due to eddy currents that are generated on a conductive surface by an external magnetic field. An AC magnetic field is generated on the detection coil, and changes in the impedance due to eddy currents generated on a metallic object are detected.
What is an inductive sensor used for?
An Inductive sensor is used to measure position . They are usually used within harsh environments as they are generally robust and can deliver stable signals even in hostile environments.
What is the working principle of inductive proximity sensor?
Inductive Proximity Sensors detect magnetic loss due to eddy currents that are generated on a conductive surface by an external magnetic field. An AC magnetic field is generated on the detection coil, and changes in the impedance due to eddy currents generated on a metallic object are detected.
What are the two types of inductive sensor?
Inductive Proximity Sensors are roughly classified into the following three types according to the operating principle: the high-frequency oscillation type using electromagnetic induction, the magnetic type using a magnet, and the capacitance type using the change in capacitance.
How does a 2 wire inductive sensor work?
2 wire DC: These sensors contain an output amplifier with the function N.O. or N.C. that can pilot a load connected in series. In this system a residual current flows through the load even when in the open state and a voltage drop occurs to the sensor when it is in the closed state.
How does a two wire proximity sensor work?
The output operation is along the two power wires in the form of a voltage drop, thus making the sensor free to work with either polarity on the common. Because of this, you can use the 2-wire sensor to replace both the NPN and PNP 3-wire models, depending on the way you wire it up.
Do inductive sensors work on stainless steel?
Inductive sensors are designed for the detection of metal targets at close range and are a popular choice for use as proximity switches in factory automation applications. Carbon steel is the typical target material for these sensors, but in some industries, stainless steel is more common.
How are inductive sensors used to measure speed?
The sensor contains a coil that is wrapped around a magnet which cause a change in the magnetic current (flux) and the coil as the teeth of a gear pass the sensor. The moving gear creates a varying flux that induces a proportional voltage in the coil of which the frequency is related to the rotation speed.
How is an inductive proximity sensor?
Working Principle of Inductive Proximity Sensor When a ferrous target enters this magnetic field, small independent electrical currents (eddy currents) which are induced on the metal’s surface. If the metal object or target is moved away from the proximity sensor, then the amplitude of the oscillator will increase.
How does a 3 wire proximity sensor work?
A 3-wire inductive proximity sensor is an electronic device that can detect ferrous (Fe) targets without any physical contact. When it detects that target, it operates an internal electronic switch. Because the sensor is an electronic device it requires a DC power source.
What is the output of an inductive sensor?
Inductive sensors with two-wire function use this common type of output with only two output cables for power supply and signal transmission. The sensor is operated in series to the connected load. In a series connection, the order in which the sensor and load are arranged is irrelevant.
Can inductive sensors detect copper?
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. But using non-ferrous metal targets decreases an inductive sensor’s sensing range.
Can inductive sensors detect aluminum?
These sensors have an equal range for aluminum and steel targets. In addition, these new inductive sensors have very long nonflush sensing ranges, allowing metals such as aluminum and stainless steel to be sensed at distances previously not possible.
What is NO and NC in sensor?
Proximity Sensors: NO (Normal Open) and NC (Normal Close).
What is the difference between capacitive and inductive proximity sensor?
Inductive proximity sensors are used for non-contact detection of metallic objects. Where Capacitive Proximity Sensors are used for non-contact detection of both metallic and nonmetallic objects such as liquid, plastic, paper and more.
How do you test an inductive proximity sensor with a multimeter?
Multimeter Test: Continuity Disconnect the wires for the sensor at its power source (Point A in the diagram). Plug the black probe into the COM (common) port on your multimeter. Set your multimeter to Continuity – the symbol looks a bit like this: •))).
What governs the size of the inductive sensor to be used?
Per the IEC specification the “test target” for an inductive proximity sensor is a piece of carbon steel (Fe360) that is 1mm thick. The size of the target is square and for a standard range sensor it is typically equal to the size of the sensor’s active surface.
Which type of material can be censored by inductive proximity sensor?
Which type of material can be sensed by inductive proximity sensor? Explanation: Metallic type of material can be sensed by inductive proximity sensor.
What kind of materials can detect an inductive proximity switch?
Inductive proximity sensors can only detect metal targets. They do not detect non-metal targets such as plastic, wood, paper, and ceramic. Unlike photoelectric sensors, this allows a inductive proximity sensor to detect a metal object through opaque plastic.
How do you test an inductive sensor?
Unplug the sensor and check that the electrical resistance of the inductive coil is roughly between 500 ohms and 1.500 ohms. If the reading value is drastically different, including zero or infinite, replace the sensor.
What are inductive proximity sensors made of?
Inductive sensor housing is typically nickel-plated brass, stainless steel, or PBT plastic.
