How to Use GLYPHMOD-2-CH-Relay: Examples, Pinouts, and Specs

The GLYPHMOD-2-CH-Relay (Manufacturer Part ID: GM-001) is a dual-channel relay module manufactured by PCBCUPID. It is designed to control high-voltage devices using low-voltage control signals, making it ideal for applications requiring electrical isolation and safety. The module features opto-isolation to protect sensitive control circuits from high-voltage spikes and interference.

• Home automation systems (e.g., controlling lights, fans, or appliances)
• Industrial control systems
• Robotics and IoT projects
• Motor and pump control
• Signal isolation in sensitive circuits

The following table outlines the key technical details of the GLYPHMOD-2-CH-Relay module:

The module has two sets of pins: Input Pins for control signals and Relay Output Terminals for connecting the load.

Each relay has three output terminals:

1. Power the Module: Connect the VCC pin to a 5V DC power source and the GND pin to the ground.
2. Control Signals: Use a microcontroller (e.g., Arduino UNO) or other control circuits to send signals to the IN1 and IN2 pins. A LOW signal activates the corresponding relay.
3. Connect the Load:
   • For devices that should turn ON when the relay is activated, connect the load between the COM and NO terminals.
   • For devices that should turn OFF when the relay is activated, connect the load between the COM and NC terminals.
4. Ensure Safety: Always ensure the load voltage and current do not exceed the module's maximum ratings (250V AC / 30V DC, 10A).

• Opto-Isolation: The module's opto-isolation ensures safety, but avoid connecting the control circuit ground to the high-voltage ground.
• Inductive Loads: When controlling inductive loads (e.g., motors), use a flyback diode across the load to suppress voltage spikes.
• Power Supply: Ensure the power supply for the module is stable and within the specified voltage range (5V DC).
• Mounting: Use the provided mounting holes to securely attach the module to a non-conductive surface.

Below is an example of how to control the GLYPHMOD-2-CH-Relay using an Arduino UNO:

// Example code to control the GLYPHMOD-2-CH-Relay with Arduino UNO

// Define the control pins for the relays
const int relay1Pin = 7; // Connect IN1 to Arduino pin 7
const int relay2Pin = 8; // Connect IN2 to Arduino pin 8

void setup() {
  // Set relay pins as outputs
  pinMode(relay1Pin, OUTPUT);
  pinMode(relay2Pin, OUTPUT);

  // Initialize relays to OFF state (HIGH signal)
  digitalWrite(relay1Pin, HIGH);
  digitalWrite(relay2Pin, HIGH);
}

void loop() {
  // Turn Relay 1 ON
  digitalWrite(relay1Pin, LOW); // Active LOW signal
  delay(1000); // Wait for 1 second

  // Turn Relay 1 OFF
  digitalWrite(relay1Pin, HIGH);
  delay(1000); // Wait for 1 second

  // Turn Relay 2 ON
  digitalWrite(relay2Pin, LOW);
  delay(1000); // Wait for 1 second

  // Turn Relay 2 OFF
  digitalWrite(relay2Pin, HIGH);
  delay(1000); // Wait for 1 second
}

1. Relays Not Activating

   • Cause: Insufficient control signal voltage.
   • Solution: Ensure the control signal voltage is between 3.3V and 5V DC.

2. Load Not Turning ON/OFF

   • Cause: Incorrect wiring of the load to the relay terminals.
   • Solution: Verify the load is connected to the correct terminals (COM, NO, or NC).

3. Module Overheating

   • Cause: Exceeding the maximum load current or voltage.
   • Solution: Ensure the load does not exceed 10A or 250V AC / 30V DC.

4. Interference in Control Signals

   • Cause: High-voltage spikes from inductive loads.
   • Solution: Use a flyback diode across the load to suppress voltage spikes.

Q1: Can I use the module with a 3.3V microcontroller?
A1: Yes, the module supports control signals as low as 3.3V DC, making it compatible with 3.3V microcontrollers like the ESP32 or Raspberry Pi.

Q2: Is the module safe for high-voltage applications?
A2: Yes, the module is designed with opto-isolation to ensure safety when controlling high-voltage devices. However, always follow proper safety precautions when working with high voltages.

Q3: Can I control both relays independently?
A3: Yes, each relay has its own control pin (IN1 and IN2), allowing independent operation.

Q4: What is the lifespan of the relays?
A4: The relays are rated for approximately 100,000 operations under normal load conditions.