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What Is the Difference Between an Open Transition & a Closed Transition?

All About Open & Closed Transition Transfer Switches

Do you know the difference between a closed and open transition? If not, we’re here to help.

For years, PSI Power & Controls has been helping commercial businesses gain access to leading products, including our automatic and manual transfer switches, as well as safety disconnects and similar products.

View our product guide to learn more about our services, contact a PSI Power & Controls team member, or read on to learn more! 

Open Transition vs. Closed Transition Transfer Switches

Automatic transfer switches are a vital part of a well-functioning backup generator system, offering a fast, safe, and effective means of changing over to generator power during incidents that leave you without utility power. But ATS products come in a wide array of types, each suited to specific applications and ideal for unique needs. Of these, closed and open transition switches are the most common and widely used. The differences seem small, but they can have an appreciable impact on your operations.

An open transition switch brings a “break before make” switch function. This means that the connection is established with the generator before the utility is shut off, and then the swap is made quickly once the connection has been safely established. Open transition switches are often regarded as the most cost-effective and widely used systems, as they are compatible and viable for most business operations and needs.

A closed transition automatic transfer switch performs a similar but slightly different function, using “make before break” features that make use of advancements in modern electrical technology. With these systems, the two power sources (utility and generator/backup) are allowed to briefly overlap, which limits or removes the momentary stutter in power that open systems can occasionally create.

And, in essence, this is the difference you’re looking at with ATS systems. Both can typically provide a perfectly acceptable solution, but there are some industries where the closed transition is more desirable. Namely, these tend to include medical facilities, industries that utilize sensitive equipment and machines, data centers, and similar businesses that would prefer to avoid that split-second change over in power.

Choose PSI Power & Controls for Electrical Solutions

Which system suits you and your commercial business’s needs best? It sometimes feels difficult to decide, but at PSI Power & Controls we would recommend speaking to one of our professionals for guidance, as well as enlisting the help of a certified and licensed electrician.

Ready to gain the advantages of an automatic transfer switch system for your business? Check our transfer switch purchasing guide to learn more!

More Information About Transfer Switches

Take a look at the following resources:

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