Why Sealed Micro Switches Are Best for Waterproof and Dustproof Devices

We all know that sealed micro switches are commonly used in equipment that needs to be waterproof and dustproof, so why are sealed micro switches suitable for use in waterproof and dustproof equipment? In this article, Unionwell will answer your questions from the basic introduction and features of sealed micro switches, and at the same time help you choose the suitable waterproof micro switch and dustproof micro switch.

What’s the Sealed Micro Switch?

Sealed Micro switch is a special type of standard micro switch, but it can be waterproof and dustproof with a protective housing to prevent ingress of moisture and particulate matter. The construction is the same as a standard micro switch and usually consists of a core structure consisting of a spring-loaded lever used to detect the lightest physical movement of an object or a change in pressure.

Feature

Small and compact design: Typically half the size of a standard micro switch, sealed micro switches are small and compact enough to be used in equipment with limited mounting conditions without compromising efficiency.

Waterproof and dustproof: Sealed micro switches are certified waterproof and dustproof to IP67 and even IP68 and withstand temperatures from -40 ℃ to 85℃.They are able to withstand extreme applications and temperatures, such as automotive, marine, dishwashers, industrial equipment, and so on.

Various terminals: Sealed switches commonly offer solder and wire-lead terminals to facilitate varied mounting and wiring needs. But Unionwell also offer a clip type terminal to cope with more diverse use environments and enable quick assembly.

Applications

Sealed IP67 micro switches excel in environments requiring precise actuation under exposure to moisture or debris, including:

• Power Tools, such as drills, saws and grinders.
• Automotive Systems, such as door locks on/off detection, and seat sensors detection.
• Marine Electronics, such as bilge pumps and navigation controls.
• Medical Devices and Security Systems.

Advantages & Disadvantages

Advantages

Long Service Life: Hermetic sealing extends operational life to millions of cycles by preventing corrosion and wear of internal contacts.

Silent: Some sealed micro switches use a sliding contact structure inside for silent operation. Slide construction means that the micro switch has a moving contact inside the micro switch next to a fixed contact, and when the micro switch is activated the moving contact slides against a fixed contact.

Wide range of applications: Due to its powerful protection, sensitive response and durability, it can be used in many areas, from daily items, such as refrigerators, dishwashers, to aerospace equipment.

Low Actuation Force: Snap-action mechanism requires minimal force to switch, enhancing sensitivity and responsiveness in control systems.

Disadvantages

Higher Cost: Advanced sealing and specialized materials increase unit cost compared to standard micro switches

Limited Electrical Ratings: Typically suited for low-power applications; not ideal for switching high currents or voltages without additional relays

Poor anti-shaking effect: Micro switches in some high-speed operation or the need to repeat the drive equipment, the switch contacts may be triggered accidentally, the occurrence of popping, resulting in the occurrence of circuit instability phenomenon.

How Does a Sealed Micro Switch Protect Against Water And Dust?

Materials

• Usually, a rubber ring or silicone material is used at the connection between the actuator and the micro switch body, which is sealed to prevent water vapor, dust, and even oil from entering the interior.
• The contacts and terminals are coated with silver or gold plated materials. 
• The housing is made of engineering plastics, metal alloys or stainless steel to resist corrosion and physical damage. Sealants such as epoxy resin and polytetrafluoroethylene (PTFE) are also used to enhance the water and dust resistance of the housing.

Production process

In the production of hermetically sealed micro switches, thermal injection molding techniques are typically used to ensure that the housings are seamless, uniform, and maintain tight tolerances and effective sealing interfaces.

How to Judge Whether the Micro Switch is Waterproof and Dustproof?

Generally, we use IP ratings to judge the water and dust resistance of micro switches, the IP (Ingress Protection) code comprises two digits: the first (0–6) rates solids protection, and the second (0–9) rates liquids protection.

First Digit (Dust Protection): Ranges from 0 (no protection) to 6 (dust-tight), indicating seal effectiveness against particles down to sub-micron levels. All the sealed micro switches are level “6”, which means complete protection against dust.

Second Digit (Water Protection): Ranges from 0 (no protection) to 9 (high-pressure, high-temperature water jets), specifying the enclosure’s ability to resist water entry under defined conditions. Sealed micro switches are level "7" to "9" with a good waterproof effect. This means that sealed micro switches can be immersed in water for a short period of time without seepage, and can even be protected from high pressure and high-temperature spray at close range.

Choosing Unionwell’s Sealed Micro Switches

Unionwell offers a range of IP-rated sealed micro switches with precise force thresholds for automotive, industrial, home appliance applications, and so on. We offer customization services including terminals, levers, and contacts to ensure product fitment. Meanwhile, Unionwell has an R&D team and after-sales team with years of experience, fully automated production lines, and testing machines to provide the most stringent quality testing to guarantee the consistency of product quality, which is the best choice for ODM and OEM.

Conclusion

Sealed micro switches combine snap-action reliability with advanced sealing technology, and have the advantages of dust and water resistance, durability, and compactness. Although they cost more and have limited electrical ratings compared to basic micro switches, their advantages in harsh environments make them indispensable in power tools, automotive systems, and marine equipment. When selecting a sealed micro switch, consider the IP rating, material, terminal style, and operating force for your application. If you would like more details and information, please contact us.