2 channel 5v relay module

🔹 2 Channel 5V Relay Module – Optocoupler Isolation

A compact dual-channel relay module designed for low-voltage microcontroller projects to safely switch higher-voltage AC/DC loads. Each channel provides complete optocoupler isolation between the control circuit and the switched load, protecting your sensitive electronics.

✅ Specifications:

• Channels: 2 Independent Relays

• Relay Type: Electromechanical (SPDT – Single Pole Double Throw)

• Contact Rating: 10A @ 250V AC / 10A @ 30V DC

• Control Signal Voltage: 5V DC (TTL Level Compatible)

• Trigger Logic: Active LOW (Relay activates when control pin goes LOW) OR jumper-selectable for Active High.

• Module Operating Voltage: 5V DC (via terminal block or header pins)

• Control Interface: Digital Input Pins (compatible with Arduino, ESP8266, Raspberry Pi via level shifter)

• Isolation: Optocoupler on each channel

• Indicators: Power LED + Channel Status LEDs

• Connections: Screw terminal blocks for Load (COM, NO, NC) & DC+/- for module power

⚙️ Features:

• Optocoupler Isolation: Protects your microcontroller from voltage spikes and electrical noise generated by the load.

• Status Indicators: LED for module power and separate LED for each relay’s ON/OFF state.

• All Necessary Components Onboard: Includes flyback diodes for relay coils, driving transistors, and pull-up resistors.

• Screw Terminals: Secure and convenient connections for both load and power wires.

• Mounting Holes: For easy and stable installation in projects.

• Jumper-Selectable Trigger Mode: Can often be configured for Active High or Active Low logic (check your specific module).

📦 Applications:

• Home automation (lighting, fans, appliances)

• IoT projects controlled via WiFi/Bluetooth

• Security systems and automated door locks

• Industrial control systems and motor drivers

• Microcontroller-based power switching for AC/DC devices

🔧 Wiring & Usage:

1. Power: Connect DC+ to 5V and DC- to GND from your power supply. (This powers the relay coils and logic.)

2. Control: Connect IN1 and IN2 to digital GPIO pins on your microcontroller (e.g., Arduino D8, D9).

3. Load: For each channel:

   • COM (Common): Connect to your power source (AC Mains Hot or DC+).

   • NO (Normally Open): Load connects here. Circuit is OPEN when relay is off, CLOSED when relay is on.

   • NC (Normally Closed): Load connects here for a circuit that is CLOSED when relay is off, OPEN when on.

4. Code Example (Arduino – Active Low):

   cpp

   #define RELAY1 8
   #define RELAY2 9
   void setup() {
     pinMode(RELAY1, OUTPUT);
     pinMode(RELAY2, OUTPUT);
     digitalWrite(RELAY1, HIGH); // Start with relay OFF
     digitalWrite(RELAY2, HIGH);
   }
   void loop() {
     digitalWrite(RELAY1, LOW);  // Turn RELAY1 ON
     delay(2000);
     digitalWrite(RELAY1, HIGH); // Turn RELAY1 OFF
     delay(2000);
   }

⚠️ Important Safety Warnings:

• High Voltage Warning: This module is designed to switch MAINS AC VOLTAGE (110V/220V). Extreme caution is required. Enclose the module completely in an insulated case. Only handle wiring with power disconnected.

• Current Rating: Do not exceed 10A per channel. For inductive loads (motors, solenoids), derate the current further.

• Power Supply: Ensure your 5V power supply can provide sufficient current (~70mA per relay coil when active).

• Load Type: Switching high DC voltages (e.g., 30V) is more challenging for relays due to arc suppression; ensure your load is within ratings.