Best Generator Interlock Kits for Safe Home Backups
If you’re seeking a safe, code-compliant way to back up your home with a portable generator, a generator interlock kit is the right solution. These kits prevent backfeeding and ensure mains and generator power can’t run at the same time. They are best for homeowners who want a reliable, switch-based method to power essential circuits during outages, while keeping all household appliances safe. The top products below are chosen for compatibility with common panels and clear installation steps. A quick comparison table follows to help you decide at a glance.
| Product | Best For | Key Spacing | Notes |
|---|---|---|---|
| Natupal Generator Interlock Kit | Square D QO/Homeline 150–200A panels | 1 3/8 inches | Solid universal fit for SD QO/Homeline |
| EXCELFU GE / BR Series Interlock Kit | Eaton Cutler Hammer 150–200A | 1 1/4–1 7/16 inches | Reliable for BR and CH series with neutral plug |
| QYZZRS Interlock Kit for Eaton | Eaton 100–125A panels | (1) specified in listing | Compact option for smaller panels |
| SPZOCE GE 150/200A Interlock | General Electric vertical GE panels | 1 1/4 inches | Simple installation with drill bit kit |
| XMK Interlock Kit for Square D QO/Homeline | Square D 100–125A panels | 3/4–7/8 inches (varies) | Lightweight option |
Natupal Generator Interlock Kit Compatible with Square D QO or Homeline Panels
Best for: Homeowners with Square D QO or Homeline 150–200A panels who need precise 1 3/8 inch spacing between main and generator breakers. This kit is designed to safely direct generator power to circuits while keeping mains OFF when in use. It’s a strong, code-friendly choice for mid-size panels and ensures reliable switching during outages. Limitations: installation requires exact alignment to the main and generator positions, so follow the included instructions carefully.
EXCELFU Interlock Kit for Eaton Cutler Hammer BR Series
Best for: Eaton Cutler Hammer BR and CH-series panels with 150–200A capacity. The kit supports a 1 1/4 to 1 7/16 inch spacing and is presented as a safe, economical way to backfeed a portable generator while preserving access to essential appliances. This option is well-suited for users who want a straightforward install and reliable performance. Caution: verify the exact model compatibility and neutral configuration before purchasing.
EXCELFU Interlock Kit for General Electric GE 150/200 Amp Panels
Best for: General Electric GE 150/200A panels. It uses a 1 1/4 inch spacing between the main and branch breakers and safely directs generator power to circuits while eliminating the risk of simultaneous power sources. Choose this if you have a GE panel and want a balanced, safe installation. Limitation: compatibility is panel-specific; check your GE model and spacing before purchase.
QYZZRS Interlock Kit for Eaton 100–125 Amp Panels
Best for: Eaton 100–125A panels. This kit emphasizes safe usage of portable power during outages and includes screws, drill bits, and labels for proper alignment. It is a compact solution for smaller electrical service panels. Caution: installation requires careful alignment to avoid mispositioning that could affect functionality.
SPZOCE Interlock Kit for GE 150/200A Panels
Best for: General Electric vertical GE panels. Spacing is 1 1/4 inch between the main and branch breakers; the kit includes a drill bit and manual for easier installation. It’s a solid choice for users who prioritize a simple setup and dependable interoperability with GE product lines. Limitation: verify the vertical panel configuration to ensure correct fit.
QYZZRS Interlock Kit for Square D QO or Homeline
Best for: Square D QO or Homeline 150–200A panels. Spacing between the main and generator breaker is 1 3/8 inches. This option appeals to users who want a consistent, listed spacing standard for common Square D installations. Caution: confirm exact panel model and available space before purchasing to avoid fit issues.
Natup Interlock Kit for GE Vertical Main Panels
Best for: General Electric vertical 150 or 200A panels. Features a 2 1/4 inch spacing between main and branch breakers, offering a different layout option for certain panel configurations. Choose this if your GE vertical panel requires a larger spacing for safe interlock. Limitation: verify that your model supports a 2 1/4 inch spacing prior to purchase.
Buying Guide
What is a generator interlock kit? It’s a mechanical device installed on a breaker panel that prevents the generator and main power from feeding the home at the same time. It directs generator power to specific circuits and reduces the risk of backfeeding, which is essential for safe generator operation during outages.
Which spacing matters most? Spacing between the main breaker and the generator/branch breakers varies by panel model. Common spacings include 1 1/4 inches, 1 3/8 inches, and larger gaps like 2 1/4 inches. The correct spacing depends entirely on your panel type and the interlock kit compatibility list.
How to choose by panel brand? Match the interlock kit to your panel brand and model: Square D QO/Homeline, Eaton/Cutler Hammer BR/CH, General Electric GE, or others. Confirm panel amperage (100–125A, 150–200A) and the exact spacing required to ensure a flush, safe fit.
Installation considerations: Some kits require drilling or drilling guides, included screws, and alignment checks with the main and generator positions. Review the installation manual for screw placement, alignment checks, and any neutral or plug-in requirements. Consider professional installation if you’re unfamiliar with breaker panels.
Safety and compliance: Interlock kits are designed to help you maintain safe electrical operation during outages and are often chosen to meet local electrical codes. Ensure the kit you select is compatible with your panel and that installation follows the manufacturer’s instructions.
FAQ
- What is an interlock kit used for? It prevents simultaneous energizing of mains and generator, directing generator power to selected circuits during outages.
- Can I install an interlock kit myself? Installation is possible for skilled DIYers, but many users opt for professional installation to ensure proper alignment and compliance.
- How do I know which spacing I need? Check your panel model and the kit’s compatibility listing for the exact spacing required between the main and generator or branch breakers.
- Are interlock kits suitable for all panel brands? No. Each kit is designed for specific brands and models; verify compatibility before purchasing.
- Do interlock kits affect circuit protection? They work with your existing breakers and do not replace them; they simply prevent backfeeding and coordinate power sources.
- Is there a risk of damaging my generator or appliances? When installed correctly, interlock kits reduce backfeed risks and help protect appliances during outages.