1. Introduction
This manual provides essential information for the safe and efficient use of your eeTao 42V AC/DC Charger, designed for the WINDHORSE W3 Electric Bike 288WH Li-ion Battery (Model: JY-420150). Please read this manual thoroughly before using the product to ensure proper operation and to prevent damage.
2. Safety Information
WARNING: To reduce the risk of fire or electric shock, do not expose this appliance to rain or moisture.
- Always ensure the charger is compatible with your device's voltage and current requirements. This charger is specifically designed for 42V Li-ion batteries.
- Do not use the charger if the cable or plug is damaged.
- Keep the charger away from water and high humidity.
- Do not disassemble the charger. Refer all servicing to qualified service personnel.
- Unplug the charger from the power outlet when not in use.
- Ensure proper ventilation around the charger during operation.
- Important Note: Rechargeable batteries have a limited lifespan, typically 1 to 3 years. If your battery is damaged or at the end of its life, it may not accept a charge, which is not an issue with the charger itself.
3. Product Overview
The eeTao 42V AC/DC Charger is a reliable power supply designed for specific electric bike batteries. It features built-in protection mechanisms to ensure safe charging.
Package Contents:
- 1 x 42V AC/DC Charger Adapter
- 1 x Power Supply Cord Cable
Key Features:
- World Wide Input Voltage: 100-240 VAC 50/60 Hz
- Output Voltage: 42V DC
- Built-in Protections:
- OVP: Over Voltage Output Protection
- OCP: Over Current Output Protection
- SCP: Short Circuit Output Protection
- Charging Indicator Light for convenience.

Figure 3.1: The eeTao 42V AC/DC Charger with its accompanying power supply cord. This image displays the main charging unit and the detachable power cable.

Figure 3.2: Illustration showing the charger's compatibility with the WINDHORSE W3 Electric Bike. Note that the electric bike itself is not included with the charger.

Figure 3.3: Close-up view of the charger's output connector, indicating it is a 5525 1-prong type with dimensions of 5.5x2.5/2.1mm. This detail is crucial for ensuring proper connection to your device.
4. Setup
- Verify Compatibility: Ensure your electric bike battery requires a 42V DC input and has a compatible charging port (5.5x2.5/2.1mm, 1-prong). This charger is specifically compatible with WINDHORSE W3 Electric Bike 288WH Li-ion Battery Model: JY-420150.
- Connect Power Cord: Plug the power supply cord cable into the charger adapter.
- Connect to Wall Outlet: Plug the power supply cord into a standard 100-240 VAC 50/60 Hz wall outlet.
- Connect to Device: Carefully insert the charger's output connector into the charging port of your electric bike battery.
5. Operating Instructions
Once connected, the charger will begin charging your battery. Observe the charging indicator light for status updates.

Figure 5.1: The charging indicator light on the charger. A red light indicates that the battery is currently charging. A green light signifies that charging is complete.
- Red Light: Indicates that the battery is currently charging.
- Green Light: Indicates that the battery is fully charged.
Once the green light appears, you may disconnect the charger from the battery and the wall outlet.
6. Maintenance
- Keep the charger clean and free from dust and debris. Use a soft, dry cloth for cleaning.
- Store the charger in a cool, dry place when not in use.
- Avoid bending or kinking the power cord excessively.
- Regularly inspect the charger and cables for any signs of damage.
7. Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| Charger light does not turn on. | No power from outlet; loose connection; damaged charger. | Check wall outlet with another device. Ensure all connections are secure. If still no light, the charger may be faulty. |
| Battery not charging (light stays green or off). | Battery is already full; battery is damaged or at end of life; incorrect battery type. | Verify battery charge level. As noted in safety information, a damaged battery will not accept charge. Ensure battery is compatible with 42V DC input. |
| Charger gets excessively hot. | Poor ventilation; faulty charger or battery. | Ensure charger is in a well-ventilated area. Discontinue use immediately if overheating occurs and contact support. |
8. Specifications
| Attribute | Detail |
|---|---|
| Brand | eeTao |
| Model Number | WINDHORSE W3 Electric Bike Charger (Compatible with JY-420150) |
| Input Voltage | 100-240 VAC, 50/60 Hz |
| Output Voltage | 42 VDC |
| Compatible Devices | Electric Bike Batteries (MODEL:JY-420150, WINDHORSE W3 Electric Bike 288WH Li-ion Battery) |
| Connector Type | Proprietary (5.5x2.5/2.1mm, 1-prong) |
| Product Dimensions | 4 x 6 x 2 inches |
| Item Weight | 3 ounces |
| Color | Black |
9. Warranty and Support
eeTao offers the following for this product:
- Refund Policy: 30 days Refund.
- Satisfaction Exchange: 24 Months Satisfaction Exchange.
For technical support or warranty claims, please contact eeTao customer service through the retailer where the product was purchased or visit the official eeTao store page on Amazon: eeTao Store.