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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 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.
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.
What will an inductive sensor read?
An inductive proximity sensor is a non-contact electronic proximity sensor. It is used for positioning and detection of metal objects. Ferrous metals, such as iron and steel, allow for a longer sensing range, while nonferrous metals, such as aluminum and copper, may reduce the sensing range by up to 60 percent.
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.
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.
What can an inductive proximity sensor detect?
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 is an inductive pick up used?
Inductive type pick-up tachometers: This magnetic pick-up is placed near a metallic toothed rotor whose speed is to be measured. As the shaft rotates, the teeth pass in front of the pick-up and produce a change in the reluctance of the magnetic circuit.
What does inductive sensor measure?
Inductive sensors are widely used to measure position or speed, especially in harsh environments.
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.
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.
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.
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 proximity sensor works?
Capacitive proximity sensors work by detecting changes in capacitance between the sensor and an object. Factors such as distance and the size of the object will affect the amount of capacitance. The sensor simply detects any changes in capacity generated between the two.
What is the sensing distance of an inductive sensor?
Inductive proximity sensors enable the detection, without contact, of metal objects at distances of up to 60 mm.
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.
Do inductive sensors work with 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 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.
Can inductive sensor detect magnet?
Magnetic proximity sensors are used for non-contact position detection beyond the normal limits of inductive sensors. Since magnetic fields penetrate all non-magnetisable materials, these sensors can detect magnets through walls made of non-ferrous metal, stainless steel, aluminum, plastic or wood.
Can Inductive sensors detect glass?
My guess is inductive and justly so because they are the most used sensor in automation today. These sensors can be used to detect objects such as glass, wood, and paper, plastic, ceramic, the list goes on and on.
Can an inductive sensor detect gold?
For detection of unique metal like gold, titanium, alloys, and others, the reduction factor 1 sensors should be able to do the job with consistent results for all metals. If a standard inductive sensor is chosen there might be a reduction factor involved depending on the metal type.
