How to Use JSY-MK-1039: Examples, Pinouts, and Specs

The JSY-MK-1039 is a compact, high-performance relay module designed for switching applications in various electronic circuits. It is equipped with multiple channels, enabling the control of multiple devices simultaneously. This module is widely used in automation and control systems, such as home automation, industrial equipment control, and IoT-based projects. Its robust design and reliable performance make it a popular choice for both hobbyists and professionals.

• Home automation systems (e.g., controlling lights, fans, or appliances)
• Industrial equipment control
• IoT-based projects requiring remote switching
• Motor control in robotics
• Security systems (e.g., activating alarms or locks)

The JSY-MK-1039 relay module is designed to handle a variety of switching tasks. Below are its key technical details:

The JSY-MK-1039 module typically features the following pin layout:

1. Power the Module: Connect the VCC pin to a 5V DC power source and the GND pin to the ground.
2. Control Signals: Connect the IN1, IN2, IN3, and IN4 pins to the control signals from a microcontroller (e.g., Arduino UNO).
3. Load Connections:
   • For each channel, connect the load to the NO (Normally Open) or NC (Normally Closed) terminal, depending on the desired behavior.
   • Connect the other end of the load to the COM terminal.
4. Triggering the Relays: Send a HIGH signal (3.3V or 5V) to the respective IN pin to activate the corresponding relay.

• Ensure the load voltage and current do not exceed the module's maximum ratings (250V AC / 30V DC, 10A).
• Use proper insulation and safety precautions when working with high voltages.
• Avoid powering the module directly from the Arduino's 5V pin if multiple relays are used simultaneously, as this may exceed the Arduino's current supply capacity. Use an external 5V power source instead.
• Use flyback diodes across inductive loads (e.g., motors) to protect the relay contacts from voltage spikes.

Below is an example of how to control the JSY-MK-1039 with an Arduino UNO:

• Connect the VCC and GND pins of the relay module to the Arduino's 5V and GND pins, respectively.
• Connect the IN1, IN2, IN3, and IN4 pins to Arduino digital pins 2, 3, 4, and 5, respectively.
• Connect a load (e.g., a light bulb) to the NO and COM terminals of Channel 1.

// Example code to control the JSY-MK-1039 relay module with an Arduino UNO

// Define the relay control pins
#define RELAY1 2  // Relay 1 control pin
#define RELAY2 3  // Relay 2 control pin
#define RELAY3 4  // Relay 3 control pin
#define RELAY4 5  // Relay 4 control pin

void setup() {
  // Set relay control pins as outputs
  pinMode(RELAY1, OUTPUT);
  pinMode(RELAY2, OUTPUT);
  pinMode(RELAY3, OUTPUT);
  pinMode(RELAY4, OUTPUT);

  // Initialize all relays to OFF state
  digitalWrite(RELAY1, LOW);
  digitalWrite(RELAY2, LOW);
  digitalWrite(RELAY3, LOW);
  digitalWrite(RELAY4, LOW);
}

void loop() {
  // Turn on Relay 1 for 2 seconds
  digitalWrite(RELAY1, HIGH);
  delay(2000);

  // Turn off Relay 1 and turn on Relay 2 for 2 seconds
  digitalWrite(RELAY1, LOW);
  digitalWrite(RELAY2, HIGH);
  delay(2000);

  // Turn off Relay 2 and turn on Relay 3 for 2 seconds
  digitalWrite(RELAY2, LOW);
  digitalWrite(RELAY3, HIGH);
  delay(2000);

  // Turn off Relay 3 and turn on Relay 4 for 2 seconds
  digitalWrite(RELAY3, LOW);
  digitalWrite(RELAY4, HIGH);
  delay(2000);

  // Turn off all relays
  digitalWrite(RELAY4, LOW);
  delay(2000);
}

1. Relays Not Activating:

   • Ensure the module is powered with a stable 5V DC supply.
   • Verify that the control signals (IN1, IN2, etc.) are receiving the correct voltage (3.3V or 5V).

2. Load Not Switching:

   • Check the wiring of the load to the NO, NC, and COM terminals.
   • Ensure the load's voltage and current are within the relay's rated limits.

3. Arduino Resets When Relays Activate:

   • This may occur if the relays draw too much current from the Arduino's 5V pin. Use an external 5V power supply for the relay module.

4. Relay Contacts Sticking:

   • This can happen if the load generates high inrush currents. Use a relay with a higher current rating or add a snubber circuit.

Q: Can I use the JSY-MK-1039 with a 3.3V microcontroller?
A: Yes, the module can be triggered with 3.3V control signals, but ensure the VCC pin is still powered with 5V DC.

Q: Is the module safe for high-voltage applications?
A: Yes, but proper insulation and safety precautions must be followed when working with voltages above 30V.

Q: Can I control AC and DC loads simultaneously?
A: Yes, as long as each load is connected to a separate relay channel and the voltage/current ratings are not exceeded.