5V 2-channel relay module with definable switching signal (high/low)
Available · 72 piece · 1-3 days
5V 8-channel relay module with definable switching signal (high/low)
Available · 100+ piece · 1-3 days
5V 1-channel relay module with definable switching signal (high/low)
Available · 100+ piece · 1-3 days
5V 4-channel relay module with definable switching signal (high/low)
Available · 100+ piece · 1-3 days
Elecrow ESP32-C6-EVB board, Wi-Fi 6 and Bluetooth 5, 4 relays, 4 opto-isolated inputs, 10A/240VAC
Available · 1 piece · 1-3 days
Soldered 1-Kanal Relaismodul, 30V DC / 250V AC, 10A, für Arduino & Mikrocontroller, Qwiic
Available · 1 piece · 1-3 days
Soldered 4-Kanal Relaismodul, 30V DC / 250V AC, 10A, für Arduino & Mikrocontroller
Available · 4 piece · 1-3 days
Soldered 1-Kanal Relaismodul, 30V DC / 250V AC, 10A, für Arduino & Mikrocontroller
Available · 4 piece · 1-3 days
DFRobot Gravity Easy Relay Module, NO/NC toggle switch, DC2.1 interface, 3.3-5.5V
Currently not available
DFRobot Gravity Digital Relay Module, Arduino & Raspberry Pi compatible, 10A, 2.8-5.5V
Currently not available
Waveshare industrial 8-channel relay module for Raspberry Pi Pico: Advanced protection functions
Currently not available
Soldered 2-Kanal Relaismodul, 30V DC / 250V AC, 10A, für Arduino & Mikrocontroller
Currently not available
Relay modules and card relays
Card relays are the perfect solution for the safe and reliable transmission of high currents and voltages, ideal for use with microcontrollers. Benefit from our many years of experience and our wide range of card relays for your project.
What are relay cards and relay modules?
Relays are circuits that allow you to control an electrical circuit by switching a smaller circuit. A relay board is a circuit board that contains several relays and allows them to be switched by a controller such as a computer or microcontroller. A relay module is a smaller version of a relay card that contains only a single relay and is often easier to use. They can be used to switch electrical devices on and off, transmit signals and control circuits.
What are relays used for?
Relay cards and modules are used in many applications where electrical devices or circuits need to be controlled remotely. Some examples of the use of relays are:
Automation of household appliances: Relays can be used to automatically switch electrical appliances such as coffee machines, washing machines or lights on and off.
Control of machines: Relays can be used to switch machines on and off and to control their functions.
Transmission of signals: Relays can be used to transmit signals from one place to another by opening or closing circuits.
Security systems: Relays can be used to control alarms or other security systems.
To use a relay, it must be connected to a controller such as a microcontroller or a computer. The controller then sends a signal to the relay to open or close the electrical circuit. In some cases, the relay can also be controlled manually by using a switch.
How can relays be used with a microcontroller?
Relays can be used with microcontrollers by connecting them to the outputs of the microcontroller. The microcontroller can then send signals to the relays to switch them. A typical connection of a relay to a microcontroller looks like this:
The signal output of the microcontroller is connected to the control input of the relay.
The circuit that the relay is to switch is connected to the contacts of the relay.
When the signal from the microcontroller is sent to the control input of the relay, the relay opens or closes the circuit.
There are different types of relays that can handle different voltages and currents, so it is important to choose the right relay for the application. It is also important to make sure that the microcontroller has enough power to control the relay.
There are also relay modules that already come with control circuitry, such as a transistor, so they can be connected directly to the outputs of a microcontroller without the need for additional circuitry.
What to consider when buying a card relay?
When buying relays, there are a few things you should consider to make sure the relay is suitable for your application:
Voltage and Current:
Make sure the relay is suitable for the voltage that will be used in your circuit.
Switching contacts:
Make sure the relay has the correct type of switching contacts for your application. Some relays have normal normally closed contacts, while others have normal normally open contacts.
Switching capacity:
Check that the relay has the required switching capacity for your application and how often the relay can be switched before it needs to be replaced.
Size:
Make sure the relay fits in the available space.
Certifications and standards:
Check the data sheet to see if the relay meets certain certifications or standards required for your application.
Manufacturer:
Choose a reliable manufacturer with a good reputation and technical support.
The best relay for your application will depend on your specific requirements and circumstances, so it pays to research carefully and consider the above factors before making a decision.