What is a Limit Switch?


limit switches

A Limit Switch is a detection switch which consists of a basic switch in a metal or resin case.
The strong outer case protects the inside of the switch from external forces, moisture, oil, dust and dirt so that it can be used in locations that demand mechanical strength and environmental resistance.


High Mechanical DurabilityThese switches will encounter significant amounts of force and shock, so the case and actuator are constructed from tough materials.
Superior Environmental ResistanceWe developed a sealed design and materials that can be used even in harsh environments with exposure to moisture, oil, dust, dirt and high or low temperatures.

Limit Switches are used in environments that demand mechanical strength or environmental resistance where normal Basic Switches could not be used.


There are two types of Limit Switches: General-purpose Vertical Types and Horizontal Types, which have superior mechanical strength.
We have a rich lineup of products in a wide variety of sizes so that you can choose the most suitable switches for your application environment.
We even offer switches that provide improvement of particular specification, such as high sealing property or high durability for use in harsh conditions.

Vertical Types
high sealing, shock resistant and strength switches
High sealing property, High shock resistance and High strength
standard switches
Standard Switches with many variations
compact and low-cost switches
Compact and Low-cost
compact and low-profile switches with a high sealing property
Compact and Low-profile with a high sealing property
Horizontal Types
high shut-off capacity switches
High-shut-off capacity and High durability
high durability, low cost switches
High durability at a low price
compact switches with high accuracy
Compact with high accuracy
compact switches with high durability
Compact with high durability
light and compact, high durability switches with a sealing property
Light and compact, High durability, High sealing property

Select the best configuration for your applications from a wide variety of external sizes and specifications.


The main components that make up a Limit Switch are the actuator, cover, bult-in switch and switch case.

switch structures


The force and movement received from the detection object are relayed to the built-in switch through the internal plunger.
The major types of actuators are roller lever, plunger and flexible rod.

actuator before operation, actuator after operation

roller lever
Roller Lever
flexible rod
Flexible Rod

Select the best actuator type based on the shape and movement of the detection object.


Attach the cover after you have wired the external connection cable to the terminal on the built-in switch.
Use rubber packing to seal the connection between the cover and the switch case.

3.Built-in Switch

The built-in switch can instantly turn ON and OFF through its snap-action mechanism.
The external movement or force reverses the movable spring and moves the moving contact from the lower NC contact to the upper NO contact.

built in switch model

4.Switch Case

The case encloses the built-in switch for protection.
Cases are made of metal or resin to increase mechanical strength.
A special connector is attached to the conduit opening on the bottom of the switch case to secure the external connection cable into place and to form a protective seal for the internal components.


Omron offers a wide array of different types of switches for different applications. Check out our product lineup for switches below.


Position Detection for Production Lines

  • Position detection for drive units (such as ones for assembly robots) and workpieces

Position Detection for Industrial Equipment and Devices

  • Open or closed detection for doors and covers on machine tools or semi-conductor manufacturing equipment

assembly robots

Assembly Robots

machine tools

Machine Tools

semiconductor manufacturing equipment

Semiconductor Manufacturing Equipment