How many mounting methods are there for proximity switches?

- Oct 11, 2019-

How many mounting methods are there for proximity switches?

There are two installation methods for general proximity switches: flush mounting and non-flush mounting;


1. Flush installation: the proximity switch head can be installed flush with the metal mounting bracket;


2. Non-flush installation: The proximity switch head cannot be installed flush with the metal mounting bracket.



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In general, proximity switches that can be flush mounted can also be mounted non-flush, but non-flush mounted proximity switches cannot be flush mounted. This is because the proximity switch head that can be flush mounted is shielded, and when it is flush mounted, it does not detect the metal mounting bracket, and the non-flush-mounted proximity switch does not have a shield. When flush mounted, it can A metal installation was detected. Because of this, the sensitivity of a non-flush-mounted proximity switch is greater than that of a flush mount, and can be selected according to actual needs in practical applications.


Note: The flush installation is a popular statement. Corresponding to our Schneider proximity sensor is embedded, non-flush installation corresponding to Schneider proximity sensor is non-buried.


How is the proximity switch installed?

First, the proximity switch is a type of switch, except that the on/off of the switch is determined by the action of the specific substance approaching and moving away. For example, the proximity switch as a limit on a general-purpose CNC machine tool controls the opening and closing of the metal block on the sensing surface. Depending on the application, the sensor can be metal, non-metal or human. The inductive switch can be divided into two lines and three lines according to the lead, and can be divided into PNP and NPN according to the polarity, and is normally open and normally closed according to the on/off state of the contact.



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The proximity switch arch line has a brown line blue line and a black line. The DC type is connected to the positive brown, the blue is connected to the negative level, and the black is the output. When the three-wire PNP is normally open, when there is no induction (multimeter DC file, red pen is connected to brown wire, black pen is connected to black wire), the black line voltage is the power supply voltage. When there is induction, the black line (the multimeter's red pen is connected to the positive pole) has a voltage of about 0v. (The corresponding plc or other device input indicator should respond at this time). Of course, the voltage between the brown line and the blue line is the power supply voltage. The voltage between the normally closed black line and the brown line is opposite to that of the normally open.


Because of this, the sensitivity of a non-flush-mounted proximity switch is greater than that of a flush mount, and can be selected according to actual needs in practical applications. The proximity sensor consists of high frequency oscillation, detection, amplification, triggering, and output circuits.


The proximity switching oscillator generates an alternating electromagnetic field on the sensor detection surface. When the metal object approaches the sensor detection surface, the eddy current generated in the metal absorbs the energy of the oscillator, so that the oscillation is weakened and the vibration is stopped. The two states of oscillation and stop vibration of the oscillator are converted into electrical signals and converted into binary switching signals by shaping amplification, and output after power amplification.


The proximity switch, which can be flush mounted, can also be mounted non-flush, but non-flush mounted proximity switches cannot be flush mounted. This is because the proximity switch head that can be flush mounted is shielded, and when it is flush mounted, it does not detect the metal mounting bracket, and the non-flush-mounted proximity switch does not have a shield. When flush mounted, it can A metal installation was detected.


Proximity switches have a displacement sensor that is "perceived" to its object. Using the displacement sensor's sensitive characteristics to the approaching object achieves the purpose of controlling the switch to open or close, which is the proximity switch. When an object moves toward the proximity switch and approaches a certain distance, the displacement sensor will "perceive" and the switch will act.


This distance is usually called the "detection distance". Different proximity switches detect different distances. Sometimes the objects being inspected are moved to the proximity switches one by one at a certain time interval, and are separated one by one, so that they are repeated continuously. Different proximity switches have different responsiveness to the detected object. This response characteristic is called the "response frequency." When the switch is approached, eddy currents are generated inside the object. This eddy current reacts to the proximity switch, causing the internal circuit parameters of the switch to change, thereby identifying whether or not the conductive object is moving closer, thereby controlling the on or off of the switch. The object that this proximity switch can detect must be an electrical conductor.


Proximity switches The measurement of such a switch is typically one plate of the capacitor and the other plate is the outer casing of the switch. This housing is usually grounded or connected to the housing of the device during the measurement process. When an object moves toward the proximity switch, whether it is a conductor or not, due to its proximity, the dielectric constant of the capacitor is always changed, so that the capacitance changes, and the state of the circuit connected to the measuring head also occurs. The switch, the proximity switch, thereby controls the switch to be turned "on" or "off". The object to be detected by the proximity switch is not limited to a conductor, a liquid or powder that can be insulated, or the like.