What Is A UBEC

What Is A UBEC [Detailed Explanation]


Most servos have a Battery Elimination Circuit(BEC). It is needed if your servo draws a big amount of current. But what if the BEC isn’t enough for it? Then UBEC can surely help you.

So, you might be thinking what is a UBEC

A UBEC (Universal Battery Elimination Circuit) has similar functionality as a BEC. But it’s more advanced when it comes to power handling. UBEC can handle higher- voltage. It converts high-voltage power to lower voltage. It also provides the voltage to run through the receiver and the servo.

That was a small introduction. To know more details about UBEC, read our piece till the end.

So, let’s begin!

What Is UBEC & How Does It Work?

As mentioned before, UBEC’s functionality is to convert high-voltage power to lower voltage. It taps power from a motor battery and tunes down the voltage. This voltage runs to the receiver and the servos.

UBEC is also the general term for a switching regulator. Specifically, those regulators that can handle high-current and high-voltage drops. 

Now, how much voltage a UBEC can handle depends on the UBEC spec. Some UBEC with good specs can handle a higher level of voltage. But the output voltage settings are usually user selectable. 

UBEC doesn’t require a separate receiver battery. It also doesn’t replace the speed controller. However, it does replace the BEC in the speed controller. 

Why Is UBEC  Needed?

What is UBEC used for?- is a very common question in RC forums. A UBEC is used in four types of scenarios. Let’s go over them-

For Higher Voltage

UBEC is used when you need high-voltage in your servo. You can always check your ESC with a multimeter to see the required current. That way you’ll know if you need a BEC or UBEC.

For High Power Servos 

When your RC requires a good amount of power, you’ll need a UBEC. BEC can supply 1-4 amperes at most. But if your servo requires more power than that, UBEC is the way to go. It can supply up to 35 voltage.


OPTO (Optical Isolated) ESC doesn’t have a built-in BEC. Instead of BEC, it uses UBEC. UBEC works as a separate power source for the receiver and servo.

For Safety 

Most of the time a BEC fails to work when the ESC malfunctions. As a result, the RC loses control and crashes. But a UBEC doesn’t fail to work when the ESC is facing malfunctioning. 

Why Use UBEC Over ESC BEC?

Most electronic speed controllers (ESC) contain a separate built-in circuit called BEC. BEC stands for Battery Eliminating Circuit. Its functionality is to supply power in the servo and receiver. It has the same functionality as UBEC.

However, in some cases using UBEC is more advantageous than using a BEC. In this segment, we’ll explain why using UBEC is more reliable than BEC.

Power Efficiency

In terms of power efficiency, UBEC is superior to BEC. BEC can convert only smaller voltages since they are linear types. UBEC is a switch type. It has more technical insight than a BEC. It can handle voltages up to 35 which is a high amount for a BEC.

UBEC is built to deal with high current power and higher-voltage drops. Thus, a UBEC is more power-efficient than a BEC. 

No Overheating Issues

BEC can handle up to 12 volts. When the input/output power is closer to this amount, it tends to overheat. When a large load is transferred the BEC overheats. When that happens sometimes the engine comes to halt.

UBEC doesn’t have overheating issues like BEC. For example, a BEC can get overheated from a 10V, but a UBEC doesn’t. Since it can handle higher voltages, it doesn’t overheat much often like BEC. So, it’s more reliable.

Current Safety

UBEC is designed to provide more current safety than BEC. Because it deals with more power. To make sure the current doesn’t harm your ESC, it’s manufactured as such.

Using UBEC is safe. But you should also choose a good ESC for your machine. Especially if it’s for your RC vehicles. Choose one from the top-quality ESC for RC cars.

These are the reasons why you can pick a UBEC over BEC.

How To Wire A UBEC?

Wiring a UBEC is not that complex. You’ve to install it in the same position where BEC is usually installed. 

Just follow these steps to wire the UBEC-

Step-1: Connection With ESC & UBEC

Connect the red (+ve) & black (-ve) wire of the UBEC with the flight battery. The same wires should go in the ESC of the RC. 

The output ESC wires are to be connected with two components. One is connected with the brushless motor and the other is with the receiver. 

Check the brushless motor with a multimeter while you’re at it. This way you can make sure the current passing through the motor is in the right amount.

Step-2: Connection With ESC & UBEC

The wires from UBEC are to be connected with the battery channel. The wires from ESC have to go to the throttle channel of the receiver. 

But here, the orange/red wire from the ESC must be removed. Simply cut and remove the wire pin from the plug.

There you go. Now, your ESC runs with UBEC instead of a BEC.


Question: What are the three wires in servo?

Answer: A servo has three wires. Ground, power, and a wire to carry the control signal. Ground wires are usually black or brown. The power supply wire is red and the control wire is white/orange.

Question: How do I know what ESC to choose?

Answer: When choosing the ESC you’ve to see the current rating in ampere. You need to know how many amperes your motor requires. The ESC should be able to provide such a current amount.

Question: What is the use of the yellow wire in a servo?

Answer: The yellow wire in the servo gives access to the feedback potentiometer. It allows you to directly measure the output’s position. Servos that contain this extra wire have a “With position feedback” label mentioned. 


That was all from us about today’s discussion on what is a UBEC? Hopefully, this discussion was informative for you. Don’t forget to use safety measurements while installing a UBEC.

Until next time!

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