This Product Selection Guide contains information to help select products in the Automotive Relays category on DigiKey.com
Automotive electromechanical relays are a specialized class designed to operate in temperature extremes, high vibration locations, and have gas and chemical ingress protection. Features may include built-in diodes or resistors, hermetic seals, flux protection, or added dust and water ingress protection. Coil types are single or double-latching or non-latching DPST, SPDT, and SPST contact forms.
SelectionCharacteristics
Coil Type: Whether the coil is latching or non-latching, single or dual coil.
Coil Current: The amount of current the coil draws when energized.
Coil Voltage: The rated voltage the relay needs to be energized.
Contact Form: Describes the contact closures provided by a relay or relay-output device, in terms of the number of independent circuits that are actuated in parallel, the number of contact positions available for each, and their default states. For more information see Switch Basics, Examples of Pole and Throw
Contact Rating (Current): Typically the maximum amount of current that a relay’s contacts are rated to interrupt when switching a resistive load. Ratings may differ for reactive loads and when switching AC or DC current.
Switching Voltage: The voltage that a relay’s output contacts are rated to interrupt.
Must Operate Voltage: The minimum voltage needed to energize the coil.
Must Release Voltage: The maximum applied voltage at which a relay must return to an inactive state.
Operate Time: Characterizes the time delay between the application of rated coil voltage and the closure (or opening) of all contacts that occurs as a result. Typically does not include contact bounce time.
Release Time: Characterizes the time delay between removal of power from the device coil and all contacts returning to their rest positions. Does not include bounce time, and may be affected by the choice of control circuitry.
Features: These are different capabilities or properties of the device such as diode, resistor, or sealed - fully.
Mounting Type: Indicates how the device is attached.
Termination Style: Selection of termination style used to connect the device to a system, such as pin, quick connect, or wire leads.
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/or other system components.
ProductExamples
| MFR PART # | 3-1393303-7 |
|---|---|
| DIGI-KEY PART # | A122267-ND |
| MANUFACTURER | TE Connectivity AMP Connectors |
| DESCRIPTION | Component Mount TO-18 Circular 0.060" (1.52mm) White |
| DATASHEET | Click Here |
| MFR PART # | CM1A-R-12V |
|---|---|
| DIGI-KEY PART # | 255-3729-ND |
| MANUFACTURER | Panasonic Electric Works |
| DESCRIPTION | Component Mount TO-18 Circular 0.060" (1.52mm) White |
| DATASHEET | Click Here |
| MFR PART # | EX2-2U1S |
|---|---|
| DIGI-KEY PART # | 399-EX2-2U1S-ND |
| MANUFACTURER | KEMET |
| DESCRIPTION | Component Mount TO-18 Circular 0.060" (1.52mm) White |
| DATASHEET | Click Here |
SchematicSymbol
Schematic symbol courtesy of Scheme-it. Please see their website for more information and symbols.
MediaLinks
Videos
How to Choose a Relay - Another Teaching Moment
Relay Basics - Another Teaching Moment
TechForum
Phoenix Contact Relay / input voltage confusion!