2-Channel 5V/12V Relay Module Low Level Trigger Board with Optocoupler for Arduino PIC AVR DSP ARM

2-Channel Relay Module — 5V / 12V, Optocoupler Isolated, Low-Level Trigger

A reliable dual-channel relay breakout module for switching AC and DC loads from microcontroller GPIO pins. Optocoupler isolation between the control circuit and relay coil protects your Arduino, ESP32, or Raspberry Pi from voltage spikes and inductive kickback — a critical safety feature when switching mains voltage loads. Each channel provides both Normally Open (NO) and Normally Closed (NC) contacts, rated for 10A at 250VAC or 30V DC.

Available in 5V and 12V coil voltage variants to match your system power supply.

Specifications

• Channels: 2 independent relay channels
• Coil Voltage: 5V DC or 12V DC (select variant)
• Trigger Mode: Low-level trigger (active LOW) / High-level trigger (active HIGH) — jumper selectable
• Isolation: Optocoupler (control circuit fully isolated from relay/load circuit)
• Relay: Songle SRD series (genuine)
• Contact Rating: 10A / 250VAC; 10A / 30VDC
• Contact Configuration: SPDT (NO + NC + COM per channel)
• Maximum Working Current: 26.8mA per channel (coil)
• Relay Life: ≥10,000,000 mechanical operations
• Indicators: Power LED + relay status LED per channel
• Terminals: KF301 screw terminals for load wiring
• Control Interface: 2.54mm pin header (VCC, GND, IN1, IN2)
• Isolation Groove: Physical separation between control and load areas (international safety standard)

Low-Level vs. High-Level Trigger

• Low-level trigger (default): Relay activates when IN pin is pulled LOW (0V / GND). Most common for Arduino — write digitalWrite(pin, LOW) to activate.
• High-level trigger: Relay activates when IN pin is driven HIGH (VCC). Use when your MCU output is active-high or when using NPN transistor drivers.

Wiring (Arduino Example)

• VCC → 5V (or 12V for 12V variant)
• GND → GND
• IN1 → Arduino digital pin (e.g. D7)
• IN2 → Arduino digital pin (e.g. D8)
• Load wires connect to COM, NO (or NC) screw terminals

Typical Applications

• Arduino/ESP32 home automation (lights, fans, appliances)
• AC mains load switching (up to 250VAC 10A)
• DC motor on/off control
• Solenoid valve control
• Smart home relay switching via IoT
• Industrial PLC output expansion
• Automatic irrigation and greenhouse control

Package Contents

• 1 × 2-channel relay module (5V or 12V coil, as selected)

Enjoy free standard shipping on all orders over $199 USD. Orders are processed within 1–2 business days.

Not satisfied? Return any item within 90 days of purchase for a full refund or exchange. Items must be in original condition.

We are committed to quality, reliability, and customer satisfaction. Every product is carefully selected and tested to meet the highest standards.