How to Use MW LRS-75-5: Examples, Pinouts, and Specs

The MW LRS-75-5 is a compact, low-cost switching power supply manufactured by Meanwell. It provides a regulated 5V DC output with a maximum current of 15A, making it ideal for powering a wide range of electronic devices and systems. Its efficient design and reliable performance make it suitable for industrial automation, LED lighting, IoT devices, and general-purpose electronics.

• Industrial control systems
• LED lighting and displays
• IoT devices and embedded systems
• DIY electronics projects
• Powering microcontrollers and single-board computers (e.g., Raspberry Pi, Arduino)

The MW LRS-75-5 has screw terminal connections for input and output. Below is the pin configuration:

1. Input Connection:

   • Connect the AC mains supply to the input terminals (L and N).
   • Ensure the frame ground (FG) is connected to earth for safety.

2. Output Connection:

   • Connect the load to the output terminals (V+ and V-).
   • Ensure the load does not exceed the maximum output current of 15A.

3. Voltage Adjustment:

   • Use the V ADJ potentiometer to fine-tune the output voltage within ±10% of 5V.

4. Mounting:

   • Secure the power supply in a well-ventilated area to prevent overheating.
   • Avoid placing the unit near heat sources or in environments with high humidity.

• Overload Protection: The LRS-75-5 includes overload protection. If the load exceeds the rated current, the power supply will enter a hiccup mode and automatically recover when the fault is removed.
• Cooling: Ensure adequate airflow around the unit to maintain proper cooling.
• Safety: Always disconnect the power supply from the mains before making any connections or adjustments.

The MW LRS-75-5 can be used to power an Arduino UNO and other peripherals. Below is an example circuit and code:

1. Connect the V+ terminal of the LRS-75-5 to the Arduino's VIN pin.
2. Connect the V- terminal of the LRS-75-5 to the Arduino's GND pin.
3. Ensure the input terminals (L and N) are connected to the AC mains supply.

// Example code to blink an LED connected to pin 13 of Arduino UNO
// Ensure the MW LRS-75-5 is providing a stable 5V to the Arduino

void setup() {
  pinMode(13, OUTPUT); // Set pin 13 as an output pin
}

void loop() {
  digitalWrite(13, HIGH); // Turn the LED on
  delay(1000);            // Wait for 1 second
  digitalWrite(13, LOW);  // Turn the LED off
  delay(1000);            // Wait for 1 second
}

1. Can I use the LRS-75-5 to power a Raspberry Pi?

   • Yes, but ensure the output voltage is set to 5V and the current demand does not exceed 15A.

2. What happens if the load exceeds 15A?

   • The power supply will enter overload protection mode (hiccup mode) and automatically recover when the load is reduced.

3. Can I use the LRS-75-5 in outdoor environments?

   • The LRS-75-5 is not weatherproof. Use it in a dry, indoor environment or within a weatherproof enclosure.

4. How do I adjust the output voltage?

   • Use a small screwdriver to turn the V ADJ potentiometer clockwise to increase or counterclockwise to decrease the voltage.

This concludes the documentation for the MW LRS-75-5. For further assistance, refer to the official Meanwell datasheet or contact technical support.