Best Breaker Interlock for Generator: Safe, Reliable Power if the Grid Fails
When backup power is essential, choosing the right breaker interlock kit is critical for safe and compliant generator backfeeding. This guide reviews five top options compatible with common panels, highlighting compatibility, spacing, installation notes, and safety features. Each product helps prevent backfeed and ensures you can run essential appliances during outages without risking main breaker conflicts or electrical faults.
| Product | Brand | Panel Compatibility | Spacing (Main to Generator) | Key Benefit |
|---|---|---|---|---|
| Natupal Generator Interlock Kit | Natupal | Square D QO or Homeline 150/200 A | 1 3/8 inches | Safe automatic transfer guidance |
| EXCELFU Generator Interlock Kit (BR Series) | EXCELFU | Eaton Cutler Hammer BR/CH 150–200 A | 1 1/4 – 1 7/16 inches | Backfeeding protection |
| QYZZRS Generator Interlock Kit (BR/CH) | QYZZRS | Eaton Cutler Hammer BR/CH 150–200 A | 1 1/4 – 1 7/16 inches | Comprehensive installation kit |
| GE Generator Interlock Kit | EXCELFU | General Electric GE 150/200 A | 1 1/4 inch | Safe, reliable backfeed control |
| MOWABI Interlock Kit | MOWABI | Square D QO/Homeline 150–200 A | 1 3/8 inches | Premium materials, solid fit |
These options cover popular panel families—Square D QO/Homeline, Eaton BR/CH, and GE—while emphasizing correct spacing and straightforward installation. Each kit aims to prevent simultaneous mains and generator energization, protecting appliances, wiring, and personnel during outages.
Natupal Interlock Kit For QO Or Homeline Panels
The Natupal interlock kit is designed for Square D QO or Homeline panels with 150 or 200 amp capacity. It specifies a 1 3/8 inch spacing between the main breaker and generator breaker, facilitating clean, safe backfeeding. The kit helps direct generator power to selected circuits during outages while ensuring the main cannot be energized simultaneously. It’s presented as a practical solution for homeowners seeking a straightforward install with reliable safety features.
Features include compatibility with popular Square D models and explicit spacing requirements to ensure proper alignment. The kit is marketed as a safeguard against accidental power loss interruptions and is positioned as a dependable means to keep essential appliances powered when the grid is down.
EXCELFU Generator Interlock Kit For BR Series
This interlock kit covers Eaton Cutler Hammer BR series 150 and 200 amp panels. It emphasizes safe backfeeding of home appliances via a portable generator and notes a spacing range from 1 1/4 to 1 7/16 inches between the main breaker and the branch breakers. The kit includes components to support a robust installation and is framed as a cost-effective safety solution for power outages, with guidance on maintaining a single active power source at a time.
Key points include compatibility with BR and CH series variants and a focus on ensuring the main and generator lines do not energize simultaneously. It’s presented as a practical method for homeowners to maintain critical loads during outages without complex wiring changes.
QYZZRS Interlock Kit For Eaton BR/CH Panels
QYZZRS offers an interlock kit compatible with Eaton Cutler Hammer BR and CH series panels in 150 or 200 amp configurations. The product specifies a spacing range of 1 1/4 to 1 7/16 inches between the main and generator breakers, with installation notes urging accurate screw placement and pre-reading of the procedure to avoid misalignment. The package is described as including an interlock plate, screws, drill bit, and labels for startup and reminders, designed to support a clean, user-friendly setup with safety at the forefront.
And while it emphasizes a safe backfeed solution, it also highlights the importance of confirming model numbers and spacing before installation to ensure compatibility and proper operation in the target panel family.
EXCELFU Interlock Kit For GE 150/200 Amp Panels
This interlock kit is designed for General Electric GE 150 or 200 amp panels. It specifies a 1 1/4 inch spacing between the main breaker and the branch breakers, and describes the safety function of preventing simultaneous main and generator energization. The kit is positioned as a safe, reliable method to direct generator power to select circuits during outages, preserving essential appliances and loads without compromising electrical safety.
Highlights include clear guidance on safe operation, a robust interlock design, and emphasis on maintaining a single power source at a time. The kit is presented as a practical option for GE panel owners seeking certified backfeeding solutions.
MOWABI Interlock Kit For Square D QO/Homeline Panels
The MOWABI interlock kit is specifically designed for Square D QO or Homeline 150–200 amp panels. It highlights a 1 3/8 inch spacing requirement and promotes premium materials for long-lasting performance, including M35 cobalt drill bits and inox screws. The kit aims to provide a reliable, bend-resistant, and easy-to-install solution for safe generator backfeeding, ensuring compatibility with the target panel family and delivering a sturdy, repeatable installation process.
In addition to fit and material quality, it emphasizes a straightforward installation approach with included hardware and instructions designed to minimize errors during mounting and alignment.
Buying Guide: Key Purchase Considerations
Panel compatibility: Confirm your main panel brand and model (Square D QO/Homeline, Eaton BR/CH, GE) and ensure the interlock kit supports 150 or 200 amp service as needed. Check the spacing specification between the main and generator breakers (common values: 1 1/4, 1 3/8, 1 7/16 inches) to match your panel’s design.
Installation requirements: Look for kits that include installation hardware, alignment aids, and clear instructions. Some kits provide drill bits, screws, labels, and test steps to ensure correct positioning before use. A straightforward bolt-on design can save time and reduce the risk of errors.
Safety features: A reliable interlock prevents simultaneous energization of mains and generator circuits, reducing the risk of backfeed, arc faults, or damage to the panel. Evaluate materials (aluminum, steel, premium alloys) and build quality for durability and long-term performance.
Compatibility depth: Some kits are offered for multiple manufacturers or panel families. If you have mixed or upgraded equipment (e.g., panels from Square D, GE, or Eaton in the same service), choose a kit with a broad compatibility range or plan panel upgrades accordingly.
Installation environment: Consider whether you need a kit that is easy to install on existing enclosures, or if you must disassemble parts of the panel for access. Read installation notes to anticipate any wiring constraints or required torque on mounting screws.
Warranty and support: Review product warranties and the availability of customer support or installation guides from the manufacturer. This helps resolve issues quickly if alignment or compatibility questions arise during installation.
Cost and value: Compare kit components, included hardware, and proven safety benefits. A kit with comprehensive installation documentation and reliable materials typically offers better long-term value than a lower-cost option with limited guidance.
Note: Prices are not included in this guide. Always follow local electrical codes and consider professional installation if you are unsure about panel compatibility or safe generator backfeeding practices.