5V Single Channel Relay Module – 10A 250V AC SPDT Optocoupler Isolated Power Switch Board for Arduino, ESP32, & Raspberry Pi

5V Single Channel Relay Module – High-Performance Opto-Isolated SPDT Power Switch for Embedded Projects

The 5V Single Channel Relay Module is the standard, rugged, and highly dependable electronic switching board deployed extensively across India for smart home automation grids, wireless IoT appliance managers, industrial machinery prototyping, and robotic power distributors. Serving as an isolated physical bridge between low-voltage microcontrollers and heavy mains appliances, this 5V Single Channel Relay Module allows standard 5V digital logic signals to safely turn high-current household appliances on or off without risking critical feedback hardware damage.

This premium variant available at VirtualPathshala integrates an advanced onboard optical optocoupler isolation barrier. By splitting the control circuitry from the physical mechanical relay coil using an internal light path, it completely eliminates ground loops and dangerous electromagnetic interference (EMI). The board is fully populated with heavy-duty PCB traces, integrated clamping transistors, and a robust flyback protection diode. Build a comprehensive remote automation cell by pairing this power switch with our selection of Arduino Uno R3 Boards, wireless ESP8266 Wi-Fi Modules, and robust multi-strand Hookup Jumper Wires.

Why Galvanic Opto-Isolation Is Mandatory for High-Voltage AC Switching

Mechanical relay coils are inherently inductive loads. When your microcontroller drops the signal line to de-energize the coil, the collapsing internal magnetic field instantly generates a massive high-voltage reverse spike (back EMF). Without proper isolation, this electrical pulse travels backward through the signal traces, causing your microcontroller to freeze, reset, or completely burn out. This premium 5V Single Channel Relay Module systematically isolates this path. The incoming digital signal drives a tiny internal LED rather than the coil directly, keeping your sensitive 32-bit processors 100% electrically isolated from high-voltage spikes.

Key Features of the 5V Single Channel Relay Module

1. High-Capacity Single-Pole Double-Throw (SPDT) Switching

The integrated mechanical sugar-cube relay houses clean, premium contacts configured in an adaptable SPDT matrix. This design gives developers complete wiring flexibility, offering both a Normally Open (NO) path that completes the circuit only when triggered, and a Normally Closed (NC) path that keeps the circuit active until an input signal tells it to break.

2. Multi-Level High/Low Trigger Signal Compatibility

The module’s logic input buffer is engineered to interface easily with various processing architectures. Requiring an ultra-low trigger current of just 5mA to 20mA, it switches reliably using standard TTL logic. This makes it fully compatible with traditional 5V Arduino lines as well as modern low-voltage 3.3V GPIO pins found on ESP32 or Raspberry Pi boards.

3. Integrated Dual LED Real-Time Status Indicators

Diagnostic testing and firmware debugging are highly simplified thanks to two distinct onboard surface-mount indicator lights. A **VCC Power LED** glows steadily whenever the board is connected to a stable 5V DC line, while a separate **Status LED** lights up immediately when the relay coil changes state, giving you instant visual feedback on your code’s performance.

4. Solderless High-Current Outer Terminal Blocks

The high-voltage side of the board is equipped with a heavy-duty, flame-retardant 3-pin screw terminal block. This feature lets you securely clamp thick household mains wiring (up to 14 AWG) directly onto the common (COM), NO, and NC contacts using a simple screwdriver, completely eliminating the need to solder high-current lines.

5. Built-in Flyback Protection and Anti-Malfunction Pull-Downs

The PCB design includes a dedicated freewheeling diode connected across the internal coil to safely clamp inductive voltage spikes. Additionally, an integrated pull-up/pull-down resistor network stabilizes the input trigger pin, preventing the relay from accidentally turning on or stuttering during microcontroller boot-up sequences.

5V Single Channel Relay Module – Full Technical Specifications

What Is Safely Included inside the Package

• ✅ 1× 5V Single Channel Relay Module (Complete Pre-Assembled Board)

Frequently Asked Questions – 5V Single Channel Relay Module

What is the functional difference between the NO and NC terminals on the screw block?

These markings define the default mechanical state of the switch contacts when no power is supplied to the relay coil. **COM** is the Common terminal where you bring in your main hot power wire. **NO (Normally Open)** acts as a broken circuit by default; it completes the path and turns on your appliance only when a digital trigger signal is sent to the input pin. Conversely, **NC (Normally Closed)** maintains a complete circuit out of the box, immediately cutting power to the connected device when the input pin is driven active.

Can I safely drive this 5V relay module using the 3.3V GPIO pins of an ESP32 or Raspberry Pi?

Yes, most modern **5V Single Channel Relay Modules** equipped with an onboard transistor driver or optocoupler handle 3.3V logic signals beautifully. However, you must still provide a full, dedicated **5V DC supply to the VCC pin** to reliably power the mechanical coil itself. The signal pin (IN) will comfortably recognize the 3.3V output from your ESP32 or Raspberry Pi as a valid logic trigger, ensuring smooth switching without overloading your microcontroller.

Can I use this compact relay module to directly control a heavy 1.5 HP water pump?

No. While the relay is rated for a 10A resistive load (like standard incandescent light bulbs or heating elements), inductive loads like large electric motors or water pumps generate massive startup current surges (inrush current) that can easily spike to 3 or 5 times their running rating. This extreme surge can arc across the tiny internal contacts, permanently welding them shut. For heavy motorized appliances, use this relay module to switch a larger, industrial-grade AC Contactor instead.

Order Your 5V Single Channel Relay Module Online Today

Safely automate your household appliances, build responsive IoT smart switches, and design isolated high-power industrial prototypes. Dispatched across all domestic Indian locations with quick, dependable express shipping options from VirtualPathshala. For official engineering data sheets, step-by-step wiring schematics, and open-source Arduino code snippets, contact our live support desk.