Backup Generator Hookups: Interlock vs Transfer Switch in Park City Homes
Understanding Backup Generator Hookups for Your Park City Home
Power outages in Park City and the surrounding Wasatch Front can be a seasonal reality, especially during winter storms or wildfire events. Having a backup generator is a reliable way to keep essential systems running when the grid goes down. But safely hooking up that generator to your home's electrical panel is just as important as the generator itself.
Two common methods for connecting a standby generator are interlock kits and transfer switches. Both prevent backfeeding electricity into the grid — a dangerous condition for utility workers and your equipment — but they do so differently. Let’s break down what each option involves and how to decide which is best for your Park City home.
What Is an Interlock Kit?
An interlock kit is an electrical device installed on your existing main service panel that physically blocks turning on the main breaker and the generator breaker at the same time. This simple mechanical interlock keeps you from inadvertently connecting the generator to the grid and causing backfeed.
Key points about interlock kits:
- They are installed inside your current electrical panel.
- You manually switch off the main breaker before switching on the generator breaker.
- They are generally less expensive than transfer switches.
- They require a generator with a specific breaker size compatible with your panel.
- Installation must be done by a licensed electrician to meet local codes and ensure safety.
What Is a Transfer Switch?
A transfer switch is a separate electrical device that safely switches the power source from the utility to your generator. There are two main types: manual transfer switches, which require you to physically switch sources, and automatic transfer switches (ATS), which switch to generator power automatically during an outage.
Key points about transfer switches:
- They isolate your home’s circuits from the grid when running on generator power.
- Can be designed to power either your entire home or selected essential circuits.
- Automatic transfer switches provide hands-off, immediate backup power.
- They tend to be more costly and require more space than interlock kits.
- Installation involves mounting the switch near your main panel and wiring it properly.
Choosing Between Interlock Kit and Transfer Switch
Here are practical factors to consider for Park City homeowners:
- Budget: Interlock kits typically cost less for installation and parts. Transfer switches, especially automatic models, are more expensive upfront.
- Convenience: Manual interlock kits require you to manually swap breakers during an outage, while ATS offers automatic switching.
- Power needs: If you want to power only a few circuits (like refrigerator, furnace, and lights), a transfer switch with selected circuits might be cleaner. Interlocks operate with your entire panel but you must manage loads to avoid overload.
- Space and aesthetics: Interlock kits fit inside your existing panel, minimizing additional equipment. Transfer switches are separate devices and need mounting space.
- Compliance and safety: Both systems must adhere to National Electrical Code (NEC) requirements. Interlock kits must be listed devices compatible with your panel. Transfer switches also must meet NEC rules and local utility standards.
NEC and Local Code Considerations
The NEC Article 702 covers Optional Standby Systems, which includes requirements for properly installing transfer equipment to prevent backfeeding. Both interlock kits and transfer switches are acceptable solutions when installed correctly.
In Utah and Summit County, utility companies require proper isolation and may have additional rules on generator interconnection, so always check with your utility and hire a licensed electrician like Scott Whiting at Whiting Design and Electric to ensure a safe, code-compliant installation.
Final Thoughts
Backup power is invaluable for Park City residents facing winter outages or unforeseen grid interruptions. Interlock kits offer an affordable, space-saving way to safely connect a generator, while transfer switches provide convenience and reliability—especially when paired with automatic models.
Consulting with a master electrician ensures your generator hookup is tailored to your home’s needs, local code, and your comfort with manual operation. If you’re considering adding backup power, reach out to Whiting Design and Electric to discuss the best interlock or transfer switch solution for your home.