Electrosurgical System: An Overview

The global electrosurgery market is expected to reach $8.8 billion by 2025.

When people hear the term “electrosurgery” they typically think of the “scalpels” and “pens” that surgeons use to perform the surgery.

But there is much more to an electrosurgical system than the handpiece.

In this blog post, we discuss the different components of an electrosurgical system and how they work together to enable electrosurgery as we know it.

Recommended: Read more about how ATL can help with your electrosurgical device.

What is an electrosurgical system?

We define an electrosurgical system as the combination of components that enable a physician to perform electrosurgery.

In our post about electrosurgical handpieces, we briefly highlighted five components of an electrosurgical system: the generator, the handpiece, the cables, the electrode, and the dispersive pad/return electrode.

For this post, we’d like to add a sixth element: the foot pedal/control.


The generator is the piece of equipment that powers the electrosurgical device.

It controls the amperage, pattern, and function (e.g., cutting, coagulating, fulgurating, etc.) of the device.

Every other piece of the electrosurgical system connects to the generator.

The face of the generator typically has a receptacle for the foot pedal and the dispersive pad/return electrode, as well as two receptacles for the handpiece (one for a monopolar device and one for a bipolar device).


The handpiece is the part of the electrosurgical system that the physician uses to perform surgery.

It is often shaped like a writing or cutting utensil to provide ergonomic support (hence the terms pen, pencil, scalpel, etc.).

For more information about electrosurgical handpieces and how they work, check out this blog post.


Cables are used to connect the generator to the handpiece, foot pedal/control, and the dispersive pad/return electrode.

To prevent confusion in the operating room, the cables that connect the various electrosurgical system components all use a different connector configuration.

For example…

The connector for the foot pedal/control is “keyed” (i.e., the male pins will only fit a specific female receptacle) differently than the connector for the dispersive pad/return electrode to prevent it from being plugged into the wrong slot.


The electrode is found on the end of the handpiece and is the part of the electrosurgical system that comes into contact with the patient.

When people use the terms “electrosurgical scalpel” or “electrosurgical forceps” they are often referring to the electrode itself.

It’s important to note that handpieces are usually configured to accept different electrodes.

Dispersive Pad/Return Electrode

Electrosurgical units are powered using an alternating current.

For an alternating current to flow through a circuit, the circuit must be closed.

During certain operations, when tools like monopolar electrodes are being used, a dispersive pad/return electrode is needed to close the circuit and “return” the energy back to the generator.

The dispersive pad/return electrode is typically placed on the patient, as near the surgical area as possible.

Foot Pedal/Control

Similar to the dispersive pad/return electrode, the foot pedal/control is not used in every electrosurgical operation.

However, in operations where the foot pedal/control pad is prevalent, it is used to control the flow of electricity running to the electrode.

How does an electrosurgical unit work?

First, it’s important to define the term “electrosurgical unit” as it can refer to either the generator or the entire electrosurgical system (e.g., generator, handpiece, foot pedal, etc.).

For the purposes of this blog post, we’ll define an electrosurgical unit as a complete electrosurgical system.

The centerpiece of an electrosurgical unit is the generator as it controls many of the functions of the rest of the system.

An electrosurgical unit works as follows:

The generator sends power to the electrode (on the end of the handpiece).

If the operation requires the electrode to cut, a continuous radio frequency (“RF”) wave is used to induce friction within the cell until it bursts.

If the operation requires the electrode to coagulate, an intermittent RF wave with a high peak is used.

With monopolar instruments, when the electrode comes into contact with the body, the current flows to the dispersive pad/return electrode and back to the generator.

With bipolar instruments, the circuit is closed by the electrode itself (there is no need for a dispersive pad/return electrode).

Throughout the process, the physician controls the flow of the current by pressing and/or releasing the foot pedal/control (similar to the accelerator in a car).

Diagram of an electrosurgical system/unit.

Additional resources.

Electrosurgical systems require a variety of interconnect components, including cables, wire harnesses, connectors, and PCBs.

To learn more about how to develop an interconnect solution that is right for your device, download our free ebook.