Features
- High safety isolation between control and load circuits
- Low-current control of high-voltage and high-current loads
- Single-channel relay output for independent load control
- High trigger input compatible with microcontrollers
- Green power indicator LED
- Red relay status indicator LED
- Normally Open and Normally Closed contacts available
- Blue screw terminals for easy and secure wiring
Principle of Work
The relay contains a control coil wound around an iron core. When a control signal energizes the coil, a magnetic field is generated, pulling the movable contact arm toward the fixed contact and closing the circuit between COM and NO. This allows current to flow to the connected load.
When the control signal is removed, the magnetic field collapses, and the spring and gravity return the contact arm to its default position, reopening the circuit or reconnecting COM to NC. This electromechanical action allows reliable switching between low-voltage control and high-power loads.
Pinout of the Module
- GND – Connect to 0V
- IN – High-level control signal input
- VCC – Connect to 12V supply
- COM – Common terminal
- NC – Normally Closed contact
- NO – Normally Open contact
Circuit
A load is connected to the NO terminal while the live wire is connected to COM. When the relay is activated, the load is powered. Alternatively, connecting the load to the NC terminal keeps it powered until the relay is triggered.
Library
This relay module does not require any additional libraries to operate.
Code
void setup() {
pinMode(2, OUTPUT);
}
void loop() {
digitalWrite(2, HIGH);
delay(1000);
digitalWrite(2, LOW);
delay(1000);
} Technical Details
- Number of Channels: 1
- Supply Voltage: 12V
- Trigger Mode: High trigger
- Trigger Current: 5mA
- Maximum Load: AC 250V / 10A, DC 30V / 10A
- Working Voltage: 12V
- Module Size: 50 x 26 x 18.5mm (L x W x H)
Applications
- Home automation systems
- Battery backup switching
- High-current load control
- Industrial and PLC control systems
- Electronic circuit switching
Comparisons
This is an active high-trigger relay module without an optocoupler. It offers a low-cost and easy-to-use solution with visible relay status indication. Compared to optocoupler-isolated relay boards, it is more susceptible to electrical noise from AC loads, which may affect sensitive microcontrollers. Electromechanical relays like this module can handle high inrush currents and high voltages with good reliability, but they are slower than solid-state relays and have a limited mechanical lifespan due to moving parts.
Features
- High safety isolation between control and load circuits
- Low-current control of high-voltage and high-current loads
- Single-channel relay output for independent load control
- High trigger input compatible with microcontrollers
- Green power indicator LED
- Red relay status indicator LED
- Normally Open and Normally Closed contacts available
- Blue screw terminals for easy and secure wiring
Principle of Work
The relay contains a control coil wound around an iron core. When a control signal energizes the coil, a magnetic field is generated, pulling the movable contact arm toward the fixed contact and closing the circuit between COM and NO. This allows current to flow to the connected load.
When the control signal is removed, the magnetic field collapses, and the spring and gravity return the contact arm to its default position, reopening the circuit or reconnecting COM to NC. This electromechanical action allows reliable switching between low-voltage control and high-power loads.
Pinout of the Module
- GND – Connect to 0V
- IN – High-level control signal input
- VCC – Connect to 12V supply
- COM – Common terminal
- NC – Normally Closed contact
- NO – Normally Open contact
Circuit
A load is connected to the NO terminal while the live wire is connected to COM. When the relay is activated, the load is powered. Alternatively, connecting the load to the NC terminal keeps it powered until the relay is triggered.
Library
This relay module does not require any additional libraries to operate.
Code
void setup() {
pinMode(2, OUTPUT);
}
void loop() {
digitalWrite(2, HIGH);
delay(1000);
digitalWrite(2, LOW);
delay(1000);
} Technical Details
- Number of Channels: 1
- Supply Voltage: 12V
- Trigger Mode: High trigger
- Trigger Current: 5mA
- Maximum Load: AC 250V / 10A, DC 30V / 10A
- Working Voltage: 12V
- Module Size: 50 x 26 x 18.5mm (L x W x H)
Applications
- Home automation systems
- Battery backup switching
- High-current load control
- Industrial and PLC control systems
- Electronic circuit switching
Comparisons
This is an active high-trigger relay module without an optocoupler. It offers a low-cost and easy-to-use solution with visible relay status indication. Compared to optocoupler-isolated relay boards, it is more susceptible to electrical noise from AC loads, which may affect sensitive microcontrollers. Electromechanical relays like this module can handle high inrush currents and high voltages with good reliability, but they are slower than solid-state relays and have a limited mechanical lifespan due to moving parts.