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What is a Shunt Trip Breaker and How Does It Work?

Written by Edwin Jones / Fact checked by Andrew Wright

what is a shunt trip breaker

What is a shunt trip breaker? Does it add protection to your electrical system?

The shunt trip breaker is a combination of the shunt trip accessory and the main circuit breaker. This installs on the main breaker to add protection to your electrical system. This adds security to your electrical system as it manually or automatically cuts the electric supply in your circuit.

This accessory can help prevent short circuits and avoid electrical damage should a disaster occur in your home.

Let me tell you more about the shunt trip breaker to help you decide if you need additional protection for your electrical system.

What is Shunt Trip Breaker and How Does It Work


You should know that shunt trip breakers are different from GFCI circuit breakers.

The GFCI circuit breaker contains one big white tail wire for neutral connections only. It cannot be connected to any control package because the GFCI circuit breaker is solely designed to detect a sudden electrical surge. It has no other purpose but to cut power in case of a short.

Meanwhile, the shunt trip breaker wiring comprises two wires. One connected to the ground, and another to a control system. The control system can be connected to a sensor or to a manual switch. When activated, the shunt trip accessory will cause the main breaker to trip.

For example, if you install a shunt trip with a smoke detector, it will activate and cut off the power should the smoke sensor trigger. It can also be installed with a remote switch, allowing you to trip your breaker manually.

It is crucial to know the difference between a regular circuit breaker and a circuit breaker installed with shunt trip accessories.

Where Are Shunt Trip Breakers Most Used


The shunt trip definition means that it is a way to cut off electrical power through other sensors, not just via thermal activation. Since this is an optional accessory for a circuit breaker, it is not required for a home electrical system.

However, it is recommended for added safety. This is especially true if you’re working with industrial machinery. Furthermore, you can use it as a manual emergency switch to shut down your main breaker.

Before installing a shunt trip, consider its cost and your existing system. You may need to change the breaker panel and circuit breakers, especially if it is not compatible with shunt trips. You may also need a new line to connect the remote emergency switch to your breaker box.

Generally, most commercial kitchens, elevators, and offices have this shunt trip breaker because it is required. Commercial kitchens use this device in compliance with ANSI/ASME CSD-1, while elevators and escalators comply with ASME A17.1. These codes refer to the controls and safety standards provided by ASME’s.

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How to Install a Shunt Trip Accessory to the Breaker

Mostly, installing a shunt trip relay requires that the breaker and the shunt be from the same maker. Also, not all breaker models are compatible with this accessory.

Once you’re sure that your system can take a shunt trip accessory, installation is pretty much straightforward. You can watch this video by Aaron CBIONE for some tutorials.

Note: Every circuit breaker comes with different instructions. It would depend on the brand and model of the breaker.

However, the critical part of every installation is that you need to connect the shunt to your sensor. You may need a shunt trip breaker diagram as a reference to ensure correct installation.

Also, check the brand and model of your breaker before proceeding with the installation. Some makers only allow a factory install of the shunt trip and other accessories. DIY installation may void the warranty of your breakers. It’s best to read up on the manual or consult an electrical professional before making any changes.


What is a shunt trip breaker? The shunt trip is an optional accessory for a circuit breaker for added protection to your system. It is designed to connect to a secondary sensor. It will trip the breaker automatically if the sensor is triggered. It can also be activated via a remote switch that you can install.

Do you think that a circuit breaker is enough to protect your investment? Or do you want an additional layer of protection for your electrical circuit? If you’re not decided yet, reach out to me in the comments section below, and I will be happy to help you.

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