Treatment of adhesion of vacuum pressure switch contacts

Adhesion of vacuum pressure switch contacts can affect its normal function, causing the equipment to fail to accurately respond to pressure changes. It can be handled from aspects such as power-off inspection, contact cleaning, contact repair and replacement, adjustment of switch parameters, optimization of the usage environment, and regular maintenance prevention. The following is a detailed introduction:

Power-off inspection

Cut off the power supply: Before conducting any processing operations, the power supply of the vacuum pressure switch must be cut off first to ensure operational safety. This is because operating with power on May lead to electric shock accidents, causing personal injury to the operators, and may also further damage the switch.

Preliminary visual inspection: Observe whether there are obvious signs of damage on the switch's appearance, such as cracked or deformed shells. These external damages may affect the sealing and stability inside the switch, thereby causing the contacts to stick together. At the same time, check whether the connection lines are loose or damaged, as line problems may also cause switch failures, indirectly leading to the adhesion of contacts.

Contact cleaning

Disassemble the switch: According to the disassembly instructions of the switch, carefully remove the casing to expose the internal contacts. During the disassembly process, it is necessary to pay attention to recording the positions and connection methods of each component so that they can be correctly assembled later.

Cleaning method: Use a clean cotton swab dipped in an appropriate amount of anhydrous alcohol to gently wipe the surface of the contact points. Anhydrous alcohol has excellent solubility and volatility, and can effectively remove oil stains, dust and oxides from the contacts. When wiping, pay attention to applying even force to avoid damaging the contacts due to excessive force. For some stubborn stains, you can gently sand the contact surface with fine sandpaper, but after sanding, clean it again with anhydrous alcohol to ensure that the contact surface is smooth and free of impurities.

Contact repair and replacement

Evaluate the condition of the contacts: Carefully inspect the degree of wear and adhesion of the contacts. If the contacts are only slightly adhered and the wear is not severe, their performance can be restored through repair. However, if the contacts have been severely worn, deformed or abeled, it is necessary to consider replacing them with new ones.

Contact repair: For slightly adhered contacts, specialized contact repair tools can be used for handling. For example, use a contact shaper to shape the contacts to restore a good contact shape. After the repair, the contact resistance of the contacts should be checked again to ensure it meets the requirements.

Contact replacement: When replacing the contacts, select those that match the original switch model. When installing new contacts, strictly follow the operating procedures to ensure that the contacts are firmly installed and in the correct position. After the replacement is completed, a comprehensive test should be conducted to check whether the switch operates flexibly and whether the contact of the contacts is good.

Adjust the switch parameters

Check the set values: Confirm whether the set values of the action pressure and reset pressure of the vacuum pressure switch are reasonable. If the set value is incorrect, it may cause the switch to act frequently and increase the risk of contact adhesion. For instance, if the operating pressure is set too low, the switch may act when the pressure fluctuates slightly, causing the contacts to remain closed for a long time and easily leading to adhesion.

Recalibrate the set values: According to the actual work requirements, use professional calibration equipment to recalibrate the set values of the switch. During the calibration process, it is necessary to strictly follow the operation instructions of the equipment to ensure the accuracy of the set values. At the same time, attention should be paid to the influence of the calibration environment, and calibration should be carried out as much as possible under stable environmental conditions.

Optimize the usage environment

Control environmental temperature and humidity: Vacuum pressure switches should be installed in an environment with suitable temperature and humidity. High-temperature environments may accelerate the oxidation and aging of contacts, while high-humidity environments are prone to causing moisture on the contact surface, increasing the possibility of adhesion. Generally speaking, the working environment temperature of the switch should be controlled between -20℃ and 70℃, and the relative humidity should not exceed 85%. If the working environment fails to meet the requirements, corresponding protective measures can be taken, such as installing heat dissipation devices and dehumidification equipment, etc.

Reduce electromagnetic interference: Avoid installing vacuum pressure switches near strong electromagnetic fields, as electromagnetic interference may affect the normal operation of the switch, causing misoperation or adhesion of the contacts. If electromagnetic interference cannot be avoided, shielding measures can be taken, such as wrapping the switch with a metal shielding cover to reduce the impact of electromagnetic interference.

Regular maintenance and prevention

Develop a maintenance plan: Establish a regular maintenance system for vacuum pressure switches, clearly defining the maintenance cycle and content. For instance, it can be stipulated that a comprehensive inspection and maintenance of the switch be carried out once every quarter, including cleaning the contacts, checking the set values, and testing the operational performance, etc.

Record maintenance status: During each maintenance process, the operation status of the switch, maintenance content and problems found should be recorded in detail. These records can provide a reference basis for subsequent maintenance and troubleshooting, helping to identify potential problems in a timely manner and take corresponding measures to handle them.