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Micro Switch Types: The Working Principle, Applications, and Benefits

Are you working on sensitive applications like fire systems or elevators? Well, the first thing you need is an electrical control system. Second, you need micro switch types.

Why do you need a micro switch? The tiny device is helpful for many applications that involve security, building, automation, etc.

We have micro slide switch types. And you need to understand how they work—to get the best one for your project. 

Let’s dive in!

What is a Micro Switch?

A microswitch is a minute snap-action device that requires little force to function.

What is a snap action switch device? It means when you touch the device with a particular stroke position, it switches instantly. And this happens without an operating force or hit operating speed. Further, you can rely on the micro safety switch for fast and efficient use. 

In addition, this switch is usually NO (normally open) or NC (normally closed).

How Does a Micro Switch Work?

Typically, when the microswitch touches an object, the contacts change position. That said, the working principle of this switch includes:

When you depress or switch the actuator;

  • The circuit that’s (NC) Normally Closed will open
  • The circuit that’s (NO) Normally Open will close

When you release the actuator, or it’s in a rest position;

  • The circuit that Normally Close will carry current
  • The Normally Open circuit can insulate electrically

Also, the micro-switches have vital features like the tipping-point mechanism. Interestingly, the feature helps to produce particular trip (operating) and reset (release) points where contacts will convert the state.

MicroSwitch Terminologies

Here are other terminologies of the microswitch that will help you understand the working principle better:

Differential Travel

This term explains the space between the operating and release point. And the idea behind separating these two points is to guard the contacts against fast and unpleasant ON/OFF. And this happens when vibration tries to shorten your switch’s operating life.

Release or Reset Point

At this point, the switch contacts go back to their regular position. 

Over-Travel

This safety feature is inside the microswitch. And it helps to stop damage to the switch. It does this by permitting the plunger to travel beyond its operating points.

Also, you have to ensure that the plunger doesn’t exceed its travel distance. Consequently, it will help to reduce damage and mechanical stress.

Trip Point or Operating

The trip point is the area where contacts change their initial state—which is an unoperated position.

Types of Micro Switches

The microswitch types include the following:

Flexible Rod

The flexible rod can rotate in any of the 3600 asides where it runs along the middle of the rod. Further, this switch has a small operating force. But it helps to indicate when there’s inconsistency in the shape or direction. Also, its plunger absorbs the overtravel. Consequently, it offers a large room in operation object play.

Hinge Roller Lever

This switch usually has a roller that attaches to its hinged lever. And it’s ideal for high-speed cam operation.

Rotating Operation

Rotating operations are pretty familiar with low-torque actuators. Hence, this switch is best-suited for identifying light objects like paper currency.

Reverse Operation Hinge Roller Lever

Most manufacturers use steel for this lever. And the switch uses a reduced torque cam and speed. Plus, it allows you to alter the shape of the level to blend with the operating body.

Spring Short Pin Plunger

Alignment is relatively easy with this switch. And it’s all thanks to its short plunger with a larger diameter. Also, overtravel is enormous.

Leaf Lever

With the leaf lever, you can generate a large stroke. All you need to do is bend in the lever. Further, you can use this switch for detecting various moving objects.

Simulated Roller Leaf Lever

This lever is a simple roller type. And you can use this switch by bending in the leaf lever. While you’re at it, ensure that the end of the device turns into a curve.

Micro Switch Types– Simulated Roller Lever

The simulated lever is yet another simple roller type on this list. You can use it by bending the end of the hinged lever into a curve.

Pin Plunger

The pin plunger is ideal for short, direct stokes. So, you can use it directly to detect high-precision positions. Also, this switch needs a reliable stopper because its overtravel has the shortest actuator.

Leaf Spring

This microswitch has a more significant stroke. And it’s because of the powerful leaf spring. Hence, you can use it for cylinder drives or low-speed cams. Also, it’s vital to maintain the switch’s overtravel within an application’s specification for two significant reasons. First, to avoid damage. Second, it’s because the leaf spring has a fixed bearing point.

Micro Switch Types– Spring Pin Plunger

When you compare the spring pin plunger to a pin plunger, you’ll notice that it has a longer overtravel. However, you can also use this micro switch for the same applications. That said when you’re using this device, ensure the load is on the plunger’s center. And this is because the diameter of the plunger is slightly larger.

Roller Leaf Spring

The difference between the leaf spring and this switch is that it comes with an attached roller. So, you can use it for cam,

Cross or Panel Mounted Roller Pin Plunger

You can operate this device with a cam. Also, it has a roller on its plunger. Even though the over travel is pretty tiny, you can adjust its position like the panel mount switch.

Micro Switch Types– Hinge Lever

The hinged lever uses a low torque cam and speed. Plus, you can change the lever’s shape to balance the operating body.

Panel Mount Pin Plunger

When you compare this plunger to other types, it has the biggest overtravel. You can mount the switch to a panel with a hexagonal locknut and nut. Then, you can operate it mechanically or manually. Plus, you can use this device alongside a low-speed cam.

Micro Switch Types– Features of MicroSwitches

  • Low sensitivity to high accelerations and vibrations
  • Compact size
  • Boosted service life
  • Reduced operating travel
  • Increased electrical properties

Advantages of Using a Micro Switch

  • It has reliable switching
  • The micro switch has a precise function
  • The device helps to reduce arcing damage, thanks to its fast switching speed
  • Microswitches are ideal for absence and presence detection. And this applies where there’s physical contact with an object. 
  • It’s also perfect for applications that need easy on-and-off actions
  • It has a set of contacts that helps to change the mechanical energy you apply to a plunger in an electrical output.
  • The micro switch is best suited if you plan to save weight and space

How to Use a Micro Switch

First, if you leave the circuit in the NC mode (unpressed lever), the LED light that links to the switch’s NC terminal glows. But if you impose a slight push on the lever terminal, the second LED light illuminates. And this happens because there’s contact between the common terminal (C) and NO terminals.

Mounting of Micro Switches

When you’re mounting side micro-switches, ensure you do it on a flat, smooth, and firm surface with the correct screw size. While you’re at it, don’t over-tighten the screws. Also, you can lock the microswitch with epoxy resin for added security.

Micro Switch Applications

  • HVAC
  • Copy machines
  • Microwave oven
  • Surveillance systems
  • Water heater

Micro Switch Types– Final words

There are different micro switch types. Some of them perform a similar function, while others do different things. So, the one you go for should depend on your project requirements. Also, it’s essential to mount your micro switches appropriately to get the best results.

Do you need help getting the best one for your projects? Please feel free to contact us.

Micro Switch Types–MicroSwitch Terminologies

Here are other terminologies of the microswitch that will help you understand the working principle better:

Differential Travel

This term explains the space between the operating and release point. And the idea behind separating these two points is to guard the contacts against fast and unpleasant ON/OFF. And this happens when vibration tries to shorten your switch’s operating life.

Release or Reset Point

At this point, the switch contacts go back to their regular position. 

Over-Travel

This safety feature is inside the microswitch. And it helps to stop damage to the switch. It does this by permitting the plunger to travel beyond its operating points.

Also, you have to ensure that the plunger doesn’t exceed its travel distance. Consequently, it will help to reduce damage and mechanical stress.

Trip Point or Operating

The trip point is the area where contacts change their initial state—which is an unoperated position.

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Hommer Zhao
Hi, I am Hommer, the founder of WellPCB. So far, we have more than 4,000 customers worldwide. If you have any questions, you can feel free to contact me. I really appreciate any help you can provide.

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