Answer first
An automatic transfer switch is the brain that disconnects the utility and connects the generator — safely, in the right order — so your home never backfeeds the grid.
01
Definition
What is this?
An ATS senses utility loss, starts or signals the generator, opens the utility connection, and closes the generator connection to selected loads. When utility returns, it reverses the sequence.
02
When to use
When does this apply?
Required for permanently installed standby systems. Essential if you want unattended operation during ice storms or travel.
03
Failure modes
What goes wrong?
Interlocking breakers done wrong. Backfeeding through a dryer outlet. Skipping grounding and neutral bonding rules. Never exercising the switch.
04
Proof
Why trust this guidance?
Hurst installs ATS equipment as part of standby packages and verifies transfer under test — not just a green light on the generator.
05
Action
What should you do next?
Ask for an ATS walkthrough during your generator sizing visit so you know which circuits are covered.
Never DIY a transfer setup that can energize utility lines — it endangers lineworkers.
Glossary
Key terms for this guide — full definitions live in the Hurst plumbing & electrical glossary.
Questions homeowners ask
FAQ
Whole-house or managed loads?
Either. Managed-load ATS setups prioritize critical circuits and can use a smaller generator.
How long until power returns?
Typically seconds to a minute after utility loss, depending on the unit and warm-up settings.
Does portable gear need an ATS?
Portables usually use manual transfer or inlet interlocks — different safety rules than automatic standby.
Author & reviewer
Hurst Electric & Plumbing
Reviewed by Hurst Electric & Plumbing
Company-level review by the licensed Hurst plumbing and electrical team in Danville, KY — a dual-trade shop. Guidance reflects how we diagnose on-site, explain scope in writing, and close out under the Hurst standard. Last updated .