1. Product Overview
The ApisQueen U5 Underwater Thruster is a powerful propulsion system designed for various remote-controlled aquatic vehicles such as boats, ROVs, and paddle boards. It features a high-efficiency motor and a bi-directional Electronic Speed Controller (ESC) for precise control.

Figure 1: ApisQueen U5 Thruster Side View

Figure 2: ApisQueen U5 Thruster Front View
2. Specifications
| Feature | Specification |
|---|---|
| Motor | 3550 |
| KV | 350 |
| Maximum Thrust (Single Thruster) | 7 Kg (15.4 LB) |
| Maximum Thrust (Two Thrusters) | 14 Kg |
| Power | 800W |
| Voltage | 12-24V (Supports up to 29.2V with fully charged battery) |
| Material | Nylon shell, PC resin propeller |
| Weight | 290g |
| Thruster Line Length | 1.5 m (default 80cm, customizable) |
| Plug Type | 4.0mm |
| ESC | 100A/XT60/4.0 |
| Mounting Hole | M4 |
Product Dimensions

Figure 3: Product Size Diagram (Dimensions: 97mm height, 96mm width, 16mm, 20mm, 30mm details)
Remote Control Specifications
| Feature | Specification |
|---|---|
| Model Type | Model boat/net pulling boat/fishing boat |
| Channels | 6 |
| RF Range | 2.4GHz (ISM 2.4006-2.4835GHz) |
| RF Power | <100mW |
| Modulation | GFSK |
| Spread Spectrum | FHSS |
| Reaction Speed | PWM: <=20ms |
| RF Distance | Water surface: 300-500m, Ground: 400-600m* |
| Receive Sensitivity | <-97dbm |
| Transmitter Voltage | 5V |
| Receiver Voltage | DC 4V-14V |
| Gross Weight | 70g |
*The remote control distance is based on actual usage, different receiver antenna models, hull characteristics, and the marked distance is only for reference.
ESC Features
- Proprietary firmware designed to improve thruster performance, providing smooth throttle response and reduced noise.
- Exclusive firmware generates regenerative braking for increased efficiency, quicker deceleration, and enhanced stability and flexibility.
- Automatic throttle signal detection on power-up, supporting 1-2ms pulse width input, Oneshot, and Multishot in normal PWM throttle mode.
- Supports Dshot150, Dshot300, and Dshot600 digital signals for strong anti-interference ability, eliminating the need for throttle stroke calibration.
- Signal wire is a twisted pair of silicone wires, increasing service life and effectively reducing interference.
Performance Test Parameters

Figure 4: ESC Test Parameters Table (Thrust vs. Voltage/Throttle)
3. Setup Instructions
Follow these steps to set up your ApisQueen U5 Underwater Thruster system. A visual demonstration is available in the video below.
Video 1: Setup and Operation Demonstration
- Turn on the Remote Control: Press the power button on the remote control. You will hear a beep, indicating it has successfully turned on.
- Connect Thruster to ESC: Connect the thruster's motor wires to the corresponding output wires of the Electronic Speed Controller (ESC). Ensure a secure connection.
- Connect ESC Receiver to Remote Control Receiver: Insert the signal cable from the ESC receiver into the first hole (Channel 1) of the remote control receiver.
- Connect ESC to Battery: Connect the ESC's power input to your battery. Upon connection, the thruster will emit a "bi-bi-bi" sound, confirming it is in working condition.

Figure 5: Thruster and ESC Connection

Figure 6: ESC and Battery Connection
4. Operating Instructions
Once the system is set up, you can operate the thruster using the remote control. The remote control allows for forward and backward propulsion.
Remote Control Functions

Figure 7: Remote Control Diagram with Button Functions
- CH1/CH2 Rocker: Controls the main propulsion (forward/backward).
- Power Switch: Turns the remote control on/off.
- Ch2 Throttle Trim: Adjusts the throttle neutral point.
- Ch1 Direction Trim: Adjusts the direction neutral point.
- Constant Speed Key: Activates/deactivates constant speed mode.
- Channel 3, 4, 5, 6 Buttons: Used for additional functions depending on the receiver type (e.g., controlling lights or other accessories).
- Charging Port: For recharging the remote control's internal battery.
- Indicator Light: Red for power supply, blue for constant speed, green for mixed control.
Receiver Function Setting Instructions
This remote control supports various receivers, including CH6 Receiver, 4+2 Receiver, and integrated receivers with brushed version power.
- CH6 Receiver: CH3 and CH5 can only use one channel at a time. CH3 is the PWM servo signal, CH5 is the power signal, mainly used to control lights or trawl hooks. CH4 and CH6 can only choose one channel to use at the same time, and CH4 is the PWM servo Signal, CH6 is the power signal.
- Integrated Receiver with Brushed Version Power: This receiver integrates the receiver and the power controller and can be customized according to customer needs.
5. Maintenance
- Fresh Water Use Only: This thruster is only suitable for fresh water use. Use in seawater is not supported and will rapidly shorten the life of the thruster.
- Secure Wiring: Ensure thruster wires are not too loose. Excessive looseness can cause wires to be sucked into the thruster, leading to damage.
- ESC Care: The ESC is anti-splash water, but it is NOT fully waterproof. Do not soak the ESC in water for a long time.
6. Troubleshooting
ESC Programming Issues
If you encounter issues with ESC programming using the assistant software:
- COM Port Not Found: If the software cannot find the COM port, you need to download and install the CH340 or CH341 driver for your computer.
- Programming Steps: Connect the computer and ESC signal cable with the USB assistant. In the software, click 'Tools', select the correct COM port, and click 'Connect'. Then, power on the ESC. Once the connection is successful, click 'Readpara' to read current parameters. Modify the desired parameters, then click 'Writepara' to save them.

Figure 8: USB Assistant for ESC Programming

Figure 9: ESC Programming Software Interface
7. User Tips
- Always double-check all connections before powering on the system to prevent accidental damage.
- Ensure the thruster is submerged in water during operation to prevent overheating and damage to the motor.
- For optimal performance and longevity, strictly adhere to fresh water use only. Saltwater exposure will significantly degrade the thruster's components.
8. Warranty and Support
For any product inquiries, technical support, or to request customized cable lengths, please contact ApisQueen customer service. Note that extended cable lengths may incur additional charges.




