This Product Selection Guide contains information to help select products in the Limit Switches category on DigiKey.com
Snap action limit switches are mechanical devices that make or break an electrical connection by closing or opening electrical contacts or solid-state circuitry when actuated by human or mechanical interaction most commonly at a travel limit position. Limit switches are selected by actuator types such as an adjustable plunger or rod, toggle, arm lever, roller, cone, leaf, rotary actuator, spring, whisker, or cable.
SelectionCharacteristics
Circuit: Describes device function in terms of a number of poles and throws, as is typical for mechanical switches. For more information please see: Switch Basics, Examples of Pole and Throw
Switch Function: Refers to the specific operation or behavior of a switch, indicating the primary purpose or mode of operation. For more information please see: Switch Basics, Examples of Pole and Throw
Current Rating (Amps): Typically this represents the maximum current to which a device will meet its given specifications. Exceeding this current may damage the device and/or other system components.
Voltage Rating - AC: Typically this represents the maximum AC voltage rating to which a device will meet its given specifications. Exceeding this voltage rating may damage the device and other system components.
Voltage Rating - DC: Typically this represents the maximum DC voltage rating to which a device will meet its given specifications. Exceeding this voltage rating may damage the device and other system components.
Actuator Type: The specific design or style of the mechanism used to change the switch position.
Mounting Type: Indicates how the device is attached.
Termination Style: Selection of termination style used to connect the device to a system, such as cable leads, PC pins, or wireless.
Ingress Protection: IP (Ingress Protection) Ratings (IP20, IP65, IP67, etc.) - Define how likely it is that water and dirt will get into the system. The first number is for dirt and solid contaminants and the second number is for water.
IP Ratings
| Protection Level | Solids | Liquids |
|---|---|---|
| 1 | Protected against solids larger than 50mm. | Protected against vertically falling drops of water. Limited Ingress permitted. |
| 2 | Protected against solids larger than 12.5mm. | Protected against vertically falling drops of water with the enclosure tilted up to 15 degrees from vertical. Limited ingress permitted. |
| 3 | Protected against solids larger than 2.5mm. | Protected against spraying water up to 60 degrees from vertical. Limited ingress permitted for 3 minutes. |
| 4 | Protected against solids larger than 1mm. | Protected against water splashing from any direction. Limited ingress permitted. |
| 5 | Protected against dust. Limited ingress of dust permitted. | Will not affect the operation of equipment for 2-8 hours. Protected against jets of water. Limited ingress permitted. |
| 6 | Dust tight. No ingress of dust 2-8 hours. | Protected against powerful jets of water. Limited ingress permitted. |
| 7 | ______________________ | Protected against the effects of immersion in 15cm-1m for 30 minutes. |
| 8 | ______________________ | Continuous immersion in water up to 3m for long periods of time. |
| 9 | ______________________ | Protected against high-pressure jets of hot water. (30 seconds) |
| 9K | ______________________ | Protected against high-pressure jets of hot water. (2 minutes) |
Features: These are different capabilities or properties of the device such as LEDs, corrosion proof, or explosion proof.
Operating Force: Refers to the amount of force required to actuate or trigger the switch.
Release Force: The amount to which the force on a switch actuator must be reduced to allow an actuated switch to return to its rest position.
Operating Position: The specific position at which the switch is intended to change its state.
Pretravel: The typical amount of actuator travel between the rest position and the actuation point of a switch.
Differential Travel: The actuator travel distance between the switch’s operation and release points; its mechanical hysteresis.
Overtravel: The amount of switch actuator movement between the operating point and mechanical travel limit.
Operating Temperature: Recommended operating temperature, typically given in a range or as a maximum. Exceeding these temperatures may affect performance or damage the device and other system components.
ProductExamples
| MFR PART # | DS-080-C PA |
|---|---|
| DIGIKEY PART # | CKN10387-ND |
| MANUFACTURER | C&K |
| DESCRIPTION | Switch SPDT Through Hole |
| DATASHEET | Click Here |
| MFR PART # | V7-1Z10E9-263 |
|---|---|
| DIGIKEY PART # | 480-6236-ND |
| MANUFACTURER | Honeywell Sensing and Productivity Solutions |
| DESCRIPTION | Switch SPDT Chassis Mount |
| DATASHEET | Click Here |
| MFR PART # | D3D-111 |
|---|---|
| DIGIKEY PART # | SW745-ND |
| MANUFACTURER | Omron Electronics Inc-EMC Div |
| DESCRIPTION | Switch SPDT Panel Mount, Snap-In |
| DATASHEET | Click Here |
| MFR PART # | D2FW-G271M(D) |
|---|---|
| DIGIKEY PART # | SW1257-ND |
| MANUFACTURER | Omron Electronics Inc-EMC Div |
| DESCRIPTION | Switch SPDT Chassis Mount |
| DATASHEET | Click Here |
| MFR PART # | ZMA00A080S06PC |
|---|---|
| DIGIKEY PART # | CKN10156-ND |
| MANUFACTURER | C&K |
| DESCRIPTION | Switch SPDT Through Hole |
| DATASHEET | Click Here |
MediaLinks
Videos
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Articles
Switch Tutorial
Product Training Modules
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