5V RELAY 10A SONGLE

🔹 5V 10A Relay Module – Songle SRD-05VDC-SL-C

A high-quality, single-channel relay module based on the popular Songle SRD-05VDC-SL-C relay. It provides a reliable, isolated switch capable of controlling high-voltage/high-current AC or DC loads with a low-voltage 5V DC control signal from a microcontroller like Arduino, Raspberry Pi, or ESP8266.

✅ Specifications:

• Relay Model: Songle SRD-05VDC-SL-C

• Control Voltage (Coil): 5V DC

• Coil Resistance: ~ 70Ω

• Coil Current: ~ 71mA (when active)

• Contact Configuration: SPDT – Single Pole Double Throw (1 Form C)

  • COM – Common Terminal

  • NO – Normally Open (Connected to COM when relay is activated)

  • NC – Normally Closed (Connected to COM when relay is deactivated)

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

• Maximum Switching: 75,000 operations (mechanical life)

• Operate/Release Time: ~10ms / ~5ms

• Module Features:

  • Optocoupler Isolation (typically 4N35 or similar) between control circuit and relay coil for protection.

  • Transistor Driver (typically S8050) with a flyback diode for the coil.

  • Status LEDs: Power indicator (usually red) and relay activation indicator (usually green or blue).

  • Screw Terminals for Load (COM, NO, NC) and DC+/- for module power.

  • Control Pins: 3-pin header (VCC, GND, IN) for connection to a microcontroller.

• Module Operating Voltage: 5V DC (for relay coil and logic)

• Control Signal (IN): Active HIGH or LOW (typically jumper-selectable)

⚙️ Key Features:

• High Current Switching: Can control appliances, motors, lamps, or solenoids up to 10A.

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

• Easy Interface: Simple 3-pin control (VCC, GND, Signal) compatible with 3.3V and 5V logic.

• Status Indication: Clear visual feedback with LEDs.

• Versatile Contact Type: SPDT configuration allows for both break-before-make switching and fail-safe (normally closed) operation.

📦 Typical Applications:

• Home Automation: Controlling lights, fans, heaters, or AC appliances via a microcontroller.

• Industrial Control: Activating pumps, motors, or solenoids in automated systems.

• Safety & Security Systems: As an isolated switch for alarms, door locks, or sirens.

• IoT Projects: Remote control of high-power devices over WiFi/Bluetooth.

• Automotive Projects: Switching high-current 12V accessories (using appropriate fuse and protection).

🔧 Wiring & Control (Arduino Example – Active High):

1. Power the Module: Connect DC+ to 5V and DC- to GND from your Arduino or a separate 5V power supply (recommended for multiple relays).

2. Control Signal: Connect the IN pin to an Arduino digital pin (e.g., D7).

3. Load Connection: Connect your high-voltage/current load:

   • For Normally Open (NO) Operation: Connect power source to COM, load to NO. Load turns ON when relay is activated.

   • For Normally Closed (NC) Operation: Connect power source to COM, load to NC. Load turns OFF when relay is activated.

4. Basic Code:
   cpp

   #define RELAY_PIN 7
   void setup() {
   pinMode(RELAY_PIN, OUTPUT);
   digitalWrite(RELAY_PIN, LOW); // Start with relay OFF
   }
   void loop() {
   digitalWrite(RELAY_PIN, HIGH); // Turn relay ON
   delay(2000);
   digitalWrite(RELAY_PIN, LOW); // Turn relay OFF
   delay(2000);
   }

⚠️ CRITICAL Safety & Usage Warnings:

• HIGH VOLTAGE WARNING: This relay can switch MAINS AC VOLTAGE (110V/220V) which is LETHAL. Extreme caution is required. Only handle wiring with power disconnected. Enclose the entire module in an insulated case for any AC application.

• Current Rating: Do not exceed 10A continuous current. For inductive loads (motors, solenoids), derate the current (use at ≤ 50-70% of rating).

• Separate Power Supply: If controlling more than 1-2 relays, power the module(s) from a separate 5V, 2A+ power supply to avoid overloading your microcontroller’s regulator.

• DC Load Caution: Switching DC loads (especially inductive) is harder on contacts than AC. For DC loads above 24V/5A, consider a solid-state relay (SSR).

• Flyback Protection: A diode is included on the module. For highly inductive loads, additional external snubber circuits (RC across contacts) are recommended.

• Heat: The relay may become warm during continuous high-current operation.