MEAN WELL LRS-50-12 Regulated Switching Power Supply User Manual

Introduction

This manual provides essential information for the safe and efficient operation of your MEAN WELL LRS-50-12 Regulated Switching Power Supply. Please read this manual thoroughly before installation and use, and retain it for future reference. This power supply is designed to convert AC input voltage to a stable 12V DC output, suitable for various electronic applications requiring 50W of power.

Safety Instructions

Electrical Hazard: Always disconnect the power supply from the AC mains before performing any installation, wiring, or maintenance.
Proper Grounding: Ensure the power supply is properly grounded to prevent electric shock.
Ventilation: Do not obstruct the ventilation openings. Adequate airflow is crucial for proper cooling and to prevent overheating.
Indoor Use Only: This device is intended for indoor use in dry environments. Do not expose to moisture, rain, or excessive humidity.
Correct Wiring: Verify all wiring connections are correct and secure before applying power. Incorrect wiring can damage the unit or connected devices.
Qualified Personnel: Installation and servicing should only be performed by qualified personnel.
Output Load: Do not exceed the maximum output current (4.2A) or power (50W) ratings to avoid damage to the power supply.

Product Overview

The MEAN WELL LRS-50-12 is a compact, single-output switching power supply. It features a universal AC input range and protections against short circuit, overload, over voltage, and over temperature.

Image: The MEAN WELL LRS-50-12 switching power supply unit, showing its compact design and terminal block for connections.

Key Features:

Universal AC input / Full range
Withstand 300VAC surge input for 5 seconds
Protections: Short circuit / Overload / Over voltage / Over temperature
Cooling by free air convection
LED indicator for power on
No load power consumption <0.2W

Setup and Installation

Follow these steps for proper installation of the LRS-50-12 power supply.

Image: Included AC input power cable with exposed wires and a 2-pin plug, and DC output cable with exposed wires and a barrel connector.

Mounting: Mount the power supply in a location that allows for adequate air circulation. Ensure there is sufficient space around the unit for cooling by free air convection.
AC Input Connection:
- Connect the AC input power cable to the L, N, and FG (Frame Ground) terminals on the power supply.
- Ensure the live (L), neutral (N), and ground (FG) wires are correctly identified and securely fastened to their respective terminals. Refer to local electrical codes for proper wiring practices.
- The provided AC cable typically has a 2-pin plug and exposed wires for connection to the power supply's terminal block.
DC Output Connection:
- Connect the DC output cable to the +V and -V terminals on the power supply.
- Ensure the positive (+) and negative (-) wires are correctly identified and securely fastened.
- Connect the other end of the DC output cable (barrel connector or exposed wires) to your intended device, ensuring polarity matches.
Verify Connections: Double-check all wiring connections for tightness and correctness before proceeding.

Operating Instructions

Power On: Once all connections are secure and verified, connect the AC input plug to a suitable power outlet. The LED indicator on the power supply should illuminate, indicating power is on.
Output Voltage: The power supply provides a regulated 12V DC output. Do not attempt to adjust the output voltage unless the unit has a specific adjustment potentiometer (not typically present on LRS-50-12 models for user adjustment).
Load Connection: Connect your device to the DC output. Ensure the device's power requirements do not exceed 12V, 4.2A, or 50W.
Power Off: To turn off the power supply, disconnect it from the AC mains outlet.

Maintenance

The LRS-50-12 power supply is designed for reliable operation with minimal maintenance. Follow these guidelines:

Cleaning: Keep the unit clean and free from dust. Use a soft, dry cloth to wipe the exterior. Do not use liquid cleaners or solvents.
Ventilation: Periodically check that the ventilation openings are not blocked by dust or debris.
Connections: Occasionally inspect wiring connections to ensure they remain secure.
Storage: If storing the unit, do so in a cool, dry place away from direct sunlight and extreme temperatures.

Troubleshooting

Problem	Possible Cause	Solution
No power / LED indicator off	No AC input power Loose AC wiring Internal fuse blown	Check AC outlet and power cord. Verify AC input connections (L, N, FG). Contact qualified service personnel.
No DC output voltage	Overload protection activated Short circuit on output Over temperature protection activated	Reduce load. Check for short circuits in the connected device/wiring. Ensure adequate ventilation; allow unit to cool.
Output voltage unstable	Poor connections Load exceeding capacity	Check all wiring connections. Ensure load is within 50W / 4.2A limits.

Specifications

Parameter	Value
Model	LRS-50-12
Input Voltage Range	100 - 240V AC (Universal)
Output Voltage	12V DC
Output Current	4.2A
Output Power	50W
Cooling Method	Free Air Convection
Protections	Short Circuit, Overload, Over Voltage, Over Temperature
Dimensions (Approx.)	(Refer to product datasheet for exact dimensions)
Weight	0.8 Pounds (approx. 12.8 ounces)

Warranty and Support

MEAN WELL products are manufactured to high-quality standards. For warranty information and technical support, please refer to the official MEAN WELL website or contact your authorized distributor. Keep your purchase receipt as proof of purchase.