1. Introduction
This manual provides essential information for the safe and efficient installation, operation, and maintenance of your Mean Well LRS-350-12 Single Output Switchable Power Supply. Please read this manual thoroughly before use and retain it for future reference.
1.1 Safety Precautions
- Ensure the power supply is disconnected from the main power source before any installation, wiring, or maintenance procedures.
- Only qualified personnel should perform installation and servicing.
- Verify the input voltage switch is set correctly for your region (115V AC or 230V AC) before connecting to power. Incorrect setting can cause damage.
- Do not operate the unit in environments with excessive moisture, dust, or extreme temperatures outside its specified range.
- Ensure proper ventilation around the unit to prevent overheating.
2. Product Features
The Mean Well LRS-350-12 power supply is designed for various industrial and electronic applications, offering robust performance and reliability. Key features include:
- AC input range selectable via a switch.
- Capable of withstanding 300 VAC surge input for 5 seconds.
- Low no-load power consumption.
- Compact 1U low profile design.
- High operating temperature capability, up to 70°C.
- Integrated protections: Short circuit, Overload, Over voltage, Over temperature.
- Built-in cooling fan with ON-OFF control.
- Compliance with UL 60950-1 safety standards.
- Withstands 5G vibration test.
- High efficiency, long operational life, and high reliability.
- LED indicator for power on status.
- 100% full load burn-in tested.
3. Specifications
Image: Mean Well LRS-350-12 348W 12V 29 Amp Single Output Switchable Power Supply. This image shows the compact metal enclosure with terminal block connections and the voltage selection switch.
| Specification | Value |
|---|---|
| Brand | MEAN WELL |
| Model Number | LRS-350-12 |
| Primary Output Voltage (VDC) | 12 V |
| Output Current (A) | 29 A |
| Maximum Output Power (W) | 350 W |
| Input Voltage (VAC) | 90 to 132 VAC, 180 to 264 VAC (Switchable) |
| Input Frequency | 47 to 63 Hz |
| Maximum Input Current (A) | 6.8 A |
| Output Connector Type | Screw Terminal Block |
| Number of Outputs | 1 |
| Form Factor | 1U |
| Item Weight | 1.2 pounds (0.54 kg) |
| Item Dimensions | 8.46 x 1.18 x 4.53 inches (215 x 30 x 115 mm) |
| Enclosure Material | Metal, Plastic |
4. Setup Instructions
4.1 Input Voltage Selection
Before connecting the power supply to the AC mains, locate the input voltage selector switch on the unit. This switch allows you to select between 115V AC and 230V AC. Ensure this switch is set to the correct voltage for your region. Incorrect selection can lead to severe damage to the power supply and connected equipment.
4.2 AC Input Connection
- Ensure the power supply is disconnected from any power source.
- Connect the AC input wires to the designated screw terminals (L, N, and Ground) on the power supply. Use appropriate gauge wiring for the current draw.
- Secure all connections firmly to prevent loose contacts.
4.3 DC Output Connection
- Connect your load to the DC output screw terminals (+V and -V). Observe correct polarity.
- Use appropriate gauge wiring for the expected DC current.
- Ensure all connections are secure.
4.4 Output Voltage Adjustment
The LRS-350-12 features an adjustable output voltage. A small potentiometer with a Phillips slot is located near the output terminals. You can fine-tune the output voltage within a specified range (typically 10V to 14.1V for the 12V model) using a small screwdriver. Adjust only when necessary and with a voltmeter connected to monitor the output.
5. Operating Instructions
5.1 Powering On
After all connections are made and verified, connect the AC input to the mains power. The LED indicator on the unit will illuminate, indicating that the power supply is active.
5.2 Cooling Fan Operation
The power supply includes a built-in cooling fan with ON-OFF control. The fan will activate automatically when the internal temperature reaches a certain threshold or when the load increases significantly. This is normal operation and helps maintain optimal performance and longevity of the unit. The fan may operate intermittently depending on the load and ambient temperature.
6. Maintenance
The Mean Well LRS-350-12 power supply is designed for long-term, reliable operation with minimal maintenance. However, periodic checks can help ensure optimal performance:
- Cleaning: Periodically inspect the unit for dust accumulation, especially around the ventilation openings and fan. Disconnect power and use compressed air or a soft brush to gently clean the surfaces.
- Connections: Ensure all input and output terminal connections remain tight and free from corrosion.
- Ventilation: Ensure that the power supply's ventilation openings are not obstructed, allowing for adequate airflow.
7. Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| No power / LED indicator off | No AC input; Incorrect input voltage switch setting; Blown fuse (external); Internal fault. | Check AC input connections and power source. Verify input voltage switch is set correctly. Check external fuses. If problem persists, discontinue use and contact support. |
| Output voltage unstable or low | Overload condition; Loose output connections; Internal fault. | Reduce load on the power supply. Check DC output wiring for secure connections. Verify output voltage adjustment. |
| Cooling fan runs frequently or loudly | High load; High ambient temperature; Obstructed ventilation. | This is often normal behavior under load. Ensure adequate ventilation around the unit. Clean any dust obstructing the fan or vents. |
| Electrical noise / Radio Frequency Interference (RFI) | Switching noise from the power supply. | Consider adding external filtering or shielding to sensitive equipment. Ensure proper grounding. |
8. Applications
The Mean Well LRS-350-12 power supply is suitable for a wide range of applications, including but not limited to:
- Industrial automation machinery
- Industrial control systems
- Mechanical and electrical equipment
- Electronic instruments, equipment, or apparatus
- 3D printers
- Amateur radio (Ham radio) setups
- LED lighting projects
9. Warranty and Support
9.1 Warranty Information
This Mean Well LRS-350-12 power supply comes with a 3-year warranty from the date of purchase. This warranty covers defects in materials and workmanship under normal use. Please retain your proof of purchase for warranty claims.
9.2 Technical Support
For technical assistance, troubleshooting beyond this manual, or warranty inquiries, please contact your authorized Mean Well distributor or reseller. Provide your product model number (LRS-350-12) and a detailed description of the issue when seeking support.
