1. Introduction
This manual provides essential instructions for the safe and efficient use of your GUY-TECH 5.9V 3A AC-DC Adapter Power Supply. Please read this manual thoroughly before use and retain it for future reference. This adapter is designed to convert alternating current (AC) from a wall outlet to direct current (DC) for compatible electronic devices, such as the yjs020f-0593000D.
2. Safety Information
Important Safety Instructions:
- Always ensure the adapter's input voltage range (AC 100V-240V) matches your power source.
- Do not expose the adapter to moisture, rain, or extreme temperatures.
- Avoid dropping or subjecting the adapter to severe impact.
- Disconnect the adapter from the power outlet when not in use for extended periods.
- This adapter features built-in protections against over voltage, over current, and short circuits to safeguard your connected devices.
- Do not attempt to open or modify the adapter. This may cause electric shock or fire.
Proposition 65 Warning: This product may contain chemicals known to the State of California to cause cancer and birth defects or other reproductive harm. For more information, visit www.P65Warnings.ca.gov.

This image illustrates the multi-protection features of the GUY-TECH AC-DC Adapter. Icons represent Over Current Protection, Over Voltage Protection, Overcharge Protection, Short Circuit Protection, Over Temperature Protection, and Anti Interference. A transparent overlay shows internal circuitry with a charging battery icon, emphasizing the internal safety mechanisms.
3. Product Overview
The GUY-TECH 5.9V 3A AC-DC Adapter is a compact and efficient power supply designed for various electronic devices. Its robust construction and integrated safety features ensure reliable performance.

This image displays the GUY-TECH 5.9V 3A AC-DC Adapter Power Supply. It features a black rectangular adapter block with a standard US two-prong plug on one side and an attached black power cord coiled at the bottom, ending in a barrel connector.
Key Features:
- Small and lightweight design for convenience and portability.
- High efficiency and low energy consumption.
- Integrated protection mechanisms for device safety, including over voltage, over current, and short circuit protection.
- Wide input voltage range (AC 100V-240V) for worldwide use.

This image provides the dimensions of the GUY-TECH AC-DC Adapter. The adapter block measures approximately 2.80 inches in length, 1.54 inches in width, and 1.18 inches in height.
4. Setup
Follow these steps to set up your GUY-TECH AC-DC Adapter:
- Verify Compatibility: Ensure your electronic device requires a 5.9V DC input with a maximum current draw of 3A and has a compatible barrel connector. Using an incompatible adapter may damage your device.
- Connect to Device: Carefully insert the barrel connector of the adapter's output cable into the power input port of your electronic device. Ensure a snug and secure connection.
- Connect to Power Outlet: Plug the AC prongs of the adapter into a standard, functional AC 100V-240V wall outlet.
- Power On: Once connected, your device should receive power. Refer to your device's own instruction manual for specific power-on procedures or indicators.
5. Operating Instructions
The GUY-TECH AC-DC Adapter operates automatically once properly connected to a power source and a compatible device. It is designed for continuous operation within its specified limits.
- The adapter maintains a stable voltage output to ensure consistent and reliable performance of your connected device.
- Avoid overloading the adapter by connecting devices that exceed its 3A output current rating. Overloading can lead to overheating and potential damage to both the adapter and the connected device.
- Always ensure adequate ventilation around the adapter during operation to prevent heat buildup.

This image shows the GUY-TECH AC-DC Adapter plugged into a white power strip, emphasizing its stable voltage delivery. Icons above indicate Over Voltage Protection, Short Circuit Protection, Overcurrent Protection, Moisture Protection, High Temperature Protection, and Stable Power Supply.
6. Specifications
| Feature | Detail |
|---|---|
| Brand | GUY-TECH |
| Model | 5.9V 3A AC-DC Adapter |
| Input Voltage | AC 100V - 240V (Worldwide Use) |
| Output Voltage | 5.9V DC |
| Output Current | 3 Amps |
| Connector Type | Barrel Plug |
| Compatible Devices | Monitors, Printers, Speakers, Tablets (requiring 5.9V 3A) |
| Special Feature | Travel-friendly design |
| Color | Black |
| Certifications | CCC, CE, RoHS |
| Manufacturer | Shenzhen Jiuzhou Power Technology Co., Ltd. |

This image presents the GUY-TECH AC-DC Adapter from an angled view, with its power cord neatly coiled. Visible labels on the adapter indicate 'AC Adapter', 'Input', 'Output', 'Model', 'MADE IN CHINA', and various certification marks (FCC, CE, RoHS).
7. Troubleshooting
If you encounter issues with your adapter, please refer to the following troubleshooting steps:
- No Power Output:
- Check if the adapter is securely plugged into the wall outlet.
- Verify that the wall outlet is functional by testing it with another device.
- Ensure the adapter's output connector is firmly inserted into your device's power port.
- Confirm that your device's power requirements (voltage and amperage) match the adapter's specifications.
- Adapter Overheating:
- If the adapter feels excessively hot, disconnect it immediately. This could indicate an overload or internal fault.
- Ensure adequate ventilation around the adapter; do not cover it.
- Confirm that the connected device does not exceed the adapter's maximum current output of 3A.
- Device Not Charging/Functioning Correctly:
- Verify that the adapter's voltage and current output precisely match your device's requirements.
- Inspect the adapter cable and connector for any visible damage or bent pins.
- Try connecting the adapter to a different power outlet.
If issues persist after performing these checks, discontinue use and contact customer support.
8. Maintenance
Proper maintenance ensures the longevity and safe operation of your adapter:
- Keep the adapter clean and free from dust. Use a soft, dry cloth for cleaning.
- Store the adapter in a cool, dry place when not in use.
- Do not attempt to open or repair the adapter. This will void any warranty and may pose a safety risk.
- Avoid bending, twisting, or crimping the power cord excessively, as this can damage internal wires.
- Regularly inspect the cable and connectors for any signs of wear or damage. If damage is found, discontinue use.
9. Warranty and Support
For warranty information or technical support regarding your GUY-TECH 5.9V 3A AC-DC Adapter Power Supply, please refer to the product packaging or contact GUY-TECH customer service through their official channels. When contacting support, please have your product model and purchase date available for efficient assistance.
