Use of proximity switches in construction machinery - Solutions - Huaqiang

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The proximity switch is a new integrated proximity switch and is an ideal electronic switching sensor. In addition to its small size, fast frequency response, wide voltage range, strong anti-interference ability, corrosion resistance and vibration resistance, it also has the advantages of no friction during use and no increase of the torque of each inductive component. The problems that should be noted when using the proximity switch in construction machinery are summarized as follows.

1 Proximity distance of the proximity switch

1) The working distance of the proximity switch is related to the material of the object to be tested. In the case of the same thickness and the sensing area, the relationship between the operating distances is S iron > S stainless steel > S brass > S aluminum > S copper;

2) The operating distance of the proximity switch has a certain relationship with the thickness and area of ​​the object to be detected (when the material of the object to be tested is the same).

2 proximity switch installation

1) A certain space should be reserved when installing the proximity switch on the metal to prevent the switch from being disturbed by other metals other than the object being detected. The metal parallel to the sensing surface should be outside the detection distance three times from the sensing surface; the metal around the axis of the switching axis should be centered near the axis of the switch, three times the diameter of the cylinder close to the diameter of the switch.

2) When installing two or more proximity switches at the same time to prevent mutual interference between the two, the switch should be opposite when the distance between the two sensing surfaces in the axial direction is greater than five times; the outer cylindrical surface when installed in parallel The distance between them should be greater than three times the length of the switch diameter. If the diameter of the switch is not equal, it should be calculated according to the diameter of the larger proximity switch.

3 Precautions during use

1) The object to be tested should not touch the proximity switch to avoid damage to the proximity switch due to friction and collision;

2) Pulling the proximity switch lead by hand can damage the proximity switch. It is best to use the line card to fix it firmly when the lead is 10 cm away from the switch.

3) If the pedal proximity switch is not applied, it is better to install a protective cover when installing;

4) The switch use distance should be set within 2/3 of the rated distance to protect against temperature and voltage. The temperature and voltage will affect the sensitivity of the proximity switch.

4 Problems to be aware of when wiring and wiring

1) The power line and power line should be kept away from the proximity switch lead. If it is unavoidable, the metal tube should be placed outside and grounded to prevent the switch from being damaged or malfunctioning.

2) It is strictly forbidden to electrify the wiring, and should be wired according to the schematic diagram of the wiring output circuit;

3) It is best not to use the output line of two proximity switches to control the same coil of the same relay, otherwise the source of the action will not be recognized, and sometimes even malfunction.