The Hobbywing UBEC 25A HV 5.2V/6V/7.4V/8.4V External Switching BEC for 3-18S LiPo is a high-current external BEC designed for large RC aircraft, helicopters, and demanding receiver-power systems. It draws power from a 3S to 18S LiPo main battery and converts it into stable receiver-side voltage for servos, receivers, gyros, flight controllers, and other onboard electronics.
With 25A continuous current and up to 50A peak current, this HV UBEC is built for servo-heavy models where a small internal ESC BEC is not enough. The high-efficiency DC-DC regulator design offers more than 90% conversion efficiency, while the metal case helps with heat dissipation and reduces electromagnetic interference.
This UBEC also supports a 1S to 2S LiPo backup power supply. If the main power supply or UBEC power path fails, the connected electronics can continue receiving power from the backup battery, making it a strong option for large fixed-wing aircraft, helicopters, and high-value RC builds where receiver-power reliability matters.
Product Specifications
| Product Name |
Hobbywing UBEC 25A HV External Switching BEC |
| Model |
UBEC-25A-HV |
| Part Number |
30606000 |
| BEC Type |
External switch-mode HV UBEC |
| Main Input Voltage |
3S-18S LiPo / 9V-80V |
| Backup Input Voltage |
1S-2S LiPo / 3V-9V |
| Output Voltage |
5.2V / 6.0V / 7.4V / 8.4V, adjustable |
| Output Current |
Continuous 25A, peak 50A |
| Output Channels |
Up to 8-channel parallel outputs |
| Efficiency |
More than 90% |
| Main Input Wires |
Red 16AWG 270mm × 1 / Black 16AWG 270mm × 1 |
| Output Interface |
3P vertical pin header; four 3P-JR male connector wires included |
| Input Connectors |
No |
| Output Connectors |
No |
| Size |
55 × 40.2 × 17.6mm |
| Weight |
74g |
Elegant Look & Powerful Core Component
The Hobbywing UBEC 25A HV uses an elegant metal case that helps dissipate heat and reduce electromagnetic interference. Inside, the high-efficiency DC-DC voltage-regulating chip works with a specially designed circuit to deliver more than 90% conversion efficiency.
Its 25A continuous current and 50A peak current meet the needs of demanding receiver-power systems, especially large helicopters, large fixed-wing aircraft, and models using multiple servos or high-current HV servo setups.
Various Functions & Different Applications
An external switch allows users to turn the UBEC output on or off easily. The wide voltage input range allows the main power supply from 3S to 18S LiPo to be connected to the UBEC, making it suitable for high-voltage RC aircraft power systems.
The output voltage is adjustable between 5.2V, 6.0V, 7.4V, and 8.4V, covering different receiver and servo voltage requirements. Up to 8 channels of parallel outputs can help distribute current to multiple connected devices, while the internal LED indicators show the working status of the UBEC and the backup power connection status.
Multiple Protections
This UBEC is designed with several protection functions for large RC models. BEC shoot-through protection helps prevent the main input voltage from directly flowing to the UBEC output if the UBEC is accidentally damaged, helping protect connected electronic devices.
It also includes over-current protection, output short-circuit protection, overheat protection, and low-voltage cutoff protection. When the main power supply voltage drops below 9V, the UBEC activates low-voltage cutoff and can switch to the backup power supply if a backup battery is connected.
Backup Power Supply
The backup power supply function allows electronic devices connected to the UBEC to receive power directly from a backup battery when the main power supply is damaged or the UBEC fails due to internal faults. This helps maintain receiver-side operation in critical situations.
The backup input supports 1S to 2S LiPo. When using a backup battery, make sure the UBEC output voltage is not set much lower than the backup battery voltage. For example, do not set the UBEC output to 5.2V while using a 2S LiPo backup battery with voltage higher than the connected electronics can safely handle.
Output Voltage Guide
-
5.2V output: Suitable for many standard receiver and servo systems.
-
6.0V output: Suitable for receivers and servos that support 6V operation.
-
7.4V output: Suitable for compatible HV receivers and HV servos.
-
8.4V output: Suitable only for compatible HV servo systems rated for 8.4V operation.
The output voltage can be changed with the built-in DIP switch. Always check the voltage rating of your receiver, gyro, flight controller, and servos before changing the UBEC output voltage.
Installation Notes
- Connect the UBEC main input wires in parallel with the main battery power supply.
- Connect a 1S to 2S LiPo backup battery if backup power operation is required.
- Plug the UBEC output into the receiver, flight controller, gyro, or servo power system as required by your model setup.
- If your brushless ESC has no built-in BEC, no ESC-side BEC change is required.
- If your brushless ESC already has a built-in BEC, disconnect the ESC’s BEC output before using this external UBEC.
- Keep the UBEC more than 5cm away from the receiver to reduce possible electromagnetic interference.
- The external switch turns the UBEC output on or off, but it does not fully disconnect the backup power supply. To completely stop backup output, disconnect the backup battery.
User Manual
For wiring diagrams, DIP-switch voltage settings, backup power notes, LED indicator details, and safety instructions, please refer to the official Hobbywing UBEC 25A HV user manual.
Recommended Applications
- Large RC helicopters using multiple servos
- Large fixed-wing aircraft with high receiver-side power demand
- 3S to 18S LiPo high-voltage aircraft power systems
- OPTO ESC systems that require a separate BEC
- HV servo setups using 7.4V or 8.4V receiver power
- Custom RC aircraft builds where backup receiver power is required
For more ESC and power-system options, explore our Hobbywing ESCs, ESC Programmers & Accessories, and External BEC & UBEC collections.
FAQ
What is the Hobbywing UBEC 25A HV used for?
It is used to provide stable power to receivers, servos, gyros, flight controllers, and other onboard electronics. It is especially useful for large helicopters, large fixed-wing aircraft, OPTO ESC setups, and servo-heavy models that need more receiver-side current than a small internal ESC BEC can provide.
Can this UBEC be used with an 18S LiPo battery?
Yes. The main input supports 3S to 18S LiPo, or 9V to 80V, making it suitable for high-voltage RC aircraft power systems.
What is the backup power supply used for?
The backup power supply allows connected electronics to receive power from a 1S to 2S LiPo backup battery if the main power supply is damaged, the main voltage drops too low, or the UBEC fails internally. It is designed to help maintain receiver-side operation in critical situations.
Should I choose 5.2V, 6.0V, 7.4V, or 8.4V output?
Choose 5.2V for standard receiver and servo setups, 6.0V for electronics that support 6V operation, and 7.4V or 8.4V only for compatible HV receivers and HV servos. Always check the voltage rating of every connected device before changing the output voltage.
Do I need to disable the ESC’s built-in BEC?
Yes, if your ESC already has a built-in BEC and you want this external UBEC to power the receiver, the ESC’s BEC output should be disconnected first. This avoids powering the receiver from two BEC outputs at the same time.
Is this product an ESC?
No. This product is not an ESC and does not control the motor. It is an external HV switching BEC used to power receivers, servos, gyros, flight controllers, and other low-voltage electronics.
