How to install the potentiometer What should be paid attention to

How to install the potentiometer?

1. When the potentiometer is installed on the panel with a nut, be very careful when tightening the nut. The tightening torque should not be too tight to avoid damage to the thread.

2. When it is necessary to install the straight sliding potentiometer with screws, avoid using too long screws, otherwise it may hinder the movement of the sliding handle and even directly damage the potentiometer itself.

3. During welding or installation, do not apply excessive force to the terminals, otherwise it may cause poor contact or mechanical damage. Try to avoid bending the terminal back and forth. The terminal may break due to bending for more than two weeks.

4. When putting the knob on the potentiometer, do not apply excessive axial push/pull force to the shaft. The push/pull force should not exceed the shaft push/pull force parameter index specified in the product specification.

When installing the potentiometer, in order to keep the performance unchanged, be sure to understand the precautions for installing the potentiometer

1. Heat dissipation problem

When the carbon film potentiometer is in use, the heat emitted from the resistor body will cause the temperature rise of the potentiometer itself. The heat must be dissipated through convection, conduction, radiation, etc., among which conduction through the chassis or bottom plate is a very important way of heat dissipation. If the potentiometer is not installed properly, the heat dissipation will be affected. It may even cause the potentiometer to be overheated and damaged. Especially those potentiometers with relatively large power consumption, coupled with the serious temperature inside the machine due to the miniaturization and morphology of electronic equipment, instruments, should pay more attention to heat dissipation. It is often installed on a metal bottom plate with good thermal conductivity to ensure good heat dissipation conditions. At the same time, it is also necessary to consider the distribution of other heating elements and devices near the potentiometer. When necessary, you should carefully consider providing ventilation and cooling conditions to ensure that the potentiometer can be used safely

2. Installation fixed problem

When installing the potentiometer, the fixing nut or the locking nut of the locking potentiometer cannot be overtightened, otherwise the rotating shaft will be deformed and the rotation will be uneven. In this way, the torque will change abnormally. For locking potentiometers, special attention should be paid if the locking torque is lower than the standard. The tightening torque is bounded by the thickness of the sleeve diameter and the material used. Generally speaking, aluminum shafts are the worst, and cast shafts, brass and steel shafts are hardened in turn. In addition, after the nut is locked, the shaft should be about 1mm higher than the surface of the nut.

3. Welding the terminal and the circuit

Since the solder tabs or leads of the potentiometer terminal are relatively short, it is necessary to pay attention to the heating temperature not to be too high when soldering in the miniaturized printed circuit board or hybrid integrated circuit. 350. C, time 35, 270. C, time 5s). otherwise. Radiant heat generated by solder baking, solder spatter, printed circuit board bending, or substrate deformation, etc., may all be the cause of failure of the carbon film potentiometer. If the wiring is wrong, you should be more careful when removing the wiring, especially when wiping the wiring from the printed circuit board or the substrate of the hybrid integrated circuit.

In addition, when soldering, use less flux as much as possible, not to let the flux immerse into the potentiometer, otherwise it will cause poor contact. In the process of soldering the circuit, between the terminals or the gaps between the terminals and the metal members, the bottom plate and other conductors, the phenomenon of soldering should be strictly avoided, and a strict removal process should be carried out after soldering.

What should be paid attention to how to install the potentiometer

1. Before soldering, the solder joints should be tinned to remove the paint and dirt on the solder joints.

2. When welding or installing the potentiometer, make the mark easy to observe.

3. The adjustable potentiometer should be installed where it is easy to adjust.

4. Heat dissipation should be considered when installing high-power potentiometers, especially to make full use of radiation heat dissipation.

5. Low-power potentiometers should use conduction heat dissipation and convection heat dissipation. Although the heat conduction of the lead of the low-power potentiometer is of decisive significance, the lead of the potentiometer mounted on the printed circuit board is better, so that the bottom plate can be used to dissipate heat.

6. When installing the potentiometer, use fastening parts to fix it firmly to avoid loosening of the potentiometer and collision with other components in the circuit. For example, some potentiometers are equipped with positioning posts on the end surface to prevent the housing from rotating. When installing, check whether the positioning posts are correctly inserted into the positioning holes on the mounting panel to avoid deformation of the housing. For rectangular trimming potentiometers fixed with screws, the screws must not be over-tightened to avoid damaging the internal structure of the potentiometer.

7. The knob installed on the shaft end of the potentiometer should not be too large, and should match the size of the potentiometer to avoid excessive adjustment of the rotating torque and damage to the internal stop of the potentiometer.

8. For potentiometers with pin-type leads, in order to prevent the leads from breaking, do not forcefully bend or twist the leads.

9. When installing the potentiometer into the circuit, pay attention to the correct connection of the three pins.

10. The welding time should be appropriate, and the heating should not be too long to avoid softening and deformation of the shell around the lead.