RELAY 5V 10A SRD-05VDC-SL-C Power Relay 5pi

The SRD-05VDC-SL-C is a high-quality 5V DC electromagnetic power relay widely used in DIY electronics, home automation, and industrial control projects. Manufactured by Songle, this relay is one of the most popular and reliable relays in the maker community, found in countless Arduino relay modules and embedded control circuits worldwide.

The relay features a Single Pole Double Throw (SPDT) configuration, meaning it can switch a load between two states: connecting the Common (COM) terminal to either the Normally Open (NO) terminal when energized, or to the Normally Closed (NC) terminal when de-energized. This dual-contact design provides maximum flexibility for circuit designers, enabling both switching and signal-routing applications.

With a rated load capacity of 10A at 250V AC and 10A at 30V DC, the SRD-05VDC-SL-C can comfortably handle lights, fans, small motors, solenoids, heating elements, and other AC/DC loads. The internal electromagnetic coil operates on a 5V DC signal with low current draw (~70 mA), making it directly compatible with microcontrollers like Arduino, ESP32, ESP8266, STM32, Raspberry Pi (with proper drive circuit), and PIC. A transistor-driver circuit with a flyback diode is typically used to interface the relay safely with logic-level outputs.

The relay is housed in a fully sealed plastic enclosure that protects the contacts and coil from dust, moisture, and contamination, ensuring long-term reliability and consistent switching performance. Its 5-pin through-hole layout is breadboard- and PCB-friendly, with a standardized footprint compatible with most relay sockets and modules.

This relay forms the heart of countless commercial and DIY relay modules, offering galvanic isolation between the control signal and the high-power load — a critical feature for safety in mains-powered applications.

Specifications

• Manufacturer: Songle
• Part Number: SRD-05VDC-SL-C
• Type: Electromagnetic Power Relay
• Configuration: SPDT (Single Pole Double Throw)
• Coil Voltage: 5V DC
• Coil Current (Typical): ~70 mA
• Coil Resistance: ~70 Ω
• Pull-In Voltage: ~3.75V DC (typical)
• Drop-Out Voltage: ~0.5V DC (typical)
• Switching Capacity:
  • 10A @ 250V AC
  • 10A @ 125V AC
  • 10A @ 30V DC
  • 10A @ 28V DC
• Maximum Switching Power: 2,500 VA / 300 W
• Maximum Switching Voltage: 250V AC / 110V DC
• Maximum Switching Current: 10A
• Contact Material: Silver Alloy
• Operate Time: ≤10 ms
• Release Time: ≤5 ms
• Mechanical Life: ≥10,000,000 operations
• Electrical Life: ≥100,000 operations (at rated load)
• Operating Temperature: -25°C to +70°C
• Number of Pins: 5 (2 coil + COM + NO + NC)
• Insulation Resistance: ≥100 MΩ at 500V DC
• Dielectric Strength: 1500V AC (between coil and contacts)
• Mounting Style: Through-Hole / PCB Mount
• Enclosure: Fully Sealed Plastic Housing
• Compliance: RoHS Compliant

Pinout

• Pin 1 & Pin 2: Coil terminals (apply 5V DC to energize)
• Pin 3 (COM): Common terminal
• Pin 4 (NC): Normally Closed contact (connected to COM when coil is OFF)
• Pin 5 (NO): Normally Open contact (connected to COM when coil is ON)

Applications

• Home Automation — controlling lights, fans, and household appliances
• Smart Home & IoT Devices — WiFi-controlled relays via ESP32/ESP8266
• Arduino Relay Modules — the standard relay used in DIY relay boards
• Motor Control — switching small AC and DC motors ON/OFF
• Lighting Control — automated indoor and outdoor lighting systems
• Garage Door Openers — remote-controlled door triggers
• Solenoid Switching — water valves, electric locks, and pneumatic controls
• Heating Elements — small heater and PTC element control
• Industrial Automation — PLC and microcontroller output stages
• Security & Alarm Systems — siren, strobe, and door-lock control
• Robotics — switching auxiliary loads from microcontroller outputs
• Aquarium & Plant Watering Systems — pump and light scheduling
• DIY Time Switches & Timers — combined with 555 timers or RTC modules
• Educational & STEM Projects — teaching relay logic and isolation
• Replacement Component — for damaged relays in existing equipment