In homes with portable generators, a generator interlock kit provides a safe, code-compliant method to backfeed power while keeping the main and generator sources from energizing simultaneously. The following selection highlights popular interlock kits compatible with leading panel brands and models. Each option focuses on reliable installation, proper spacing between breakers, and practical safety benefits for outages and emergencies.
| Product | Brand | Panel Compatibility | Spacing (approx.) |
|---|---|---|---|
| Natupal Generator Interlock Kit | Natupal | Square D QO or Homeline 150/200 A | 1 3/8 inches |
| QYZZRS Interlock Kit for BR/CH | QYZZRS | Eaton Cutler Hammer BR/CH 150/200 A | 1 1/4″ – 1 7/16″ |
| QYZZRS Interlock Kit for Square D QO/ Homeline | QYZZRS | Square D QO or Homeline 150/200 A | 1 3/8 inches |
| EXCELFU Interlock Kit for BR Series | EXCELFU | Eaton/Cutler Hammer BR/CH 150/200 A | 1 1/4″ – 1 7/16″ |
| XMK Interlock Kit for Siemens/Murray | XMK | Siemens/Murray 150/200 A | 7/8″ – 1 1/4″ |
These kits are designed to help homeowners safely backfeed a portable generator, preventing backfeed into the utility lines and avoiding simultaneous energizing of mains and generator power. When selecting a kit, consider panel model compatibility, the exact spacing required between the main and generator/branch breakers, and installation steps provided in the kit’s documentation. The right interlock kit supports consistent operation during outages and protects electrical equipment and personnel.
Natupal Interlock Kit For Square D QO or Homeline
Compatibility and spacing are key. This Natupal kit is designed for Square D QO or Homeline panels rated at 150 or 200 amps, with a recommended 1 3/8 inch spacing between the main and generator breaker. The kit aims to simplify safe power transfer during outages, directing generator power to circuits while ensuring main power remains isolated when needed. Installation requires attention to alignment and screws placement to ensure proper function and safety.
QYZZRS Interlock Kit For BR/CH Series
This interlock kit suits Eaton Cutler Hammer BR and CH series panels at 150 and 200 amps. It specifies a spacing range of 1 1/4 to 1 7/16 inches between the main and generator breakers. The installation guidance emphasizes verifying model numbers and spacing, and following a test simulation to align the kit correctly, reducing the risk of misalignment and unusable configurations in operation.
QYZZRS Square D QO/ Homeline Interlock Kit
This kit targets Square D QO and Homeline 150/200 amp panels, offering a 1 3/8 inch spacing between the main and generator breaker. The installation notes recommend attaching screws to the interlock first and performing a test alignment before final mounting to ensure correct positioning and optimal function during power transfers.
EXCELFU Interlock Kit For BR Series
Safe and reliable operation is highlighted for this EXCELFU kit, designed for Eaton/Cutler Hammer BR and CH series panels at 150 and 200 amps. It notes a spacing range of 1 1/4 to 1 7/16 inches and emphasizes a test-first installation approach—screws should be attached to the kit prior to installation, with alignment checks to prevent misalignment and ensure proper backfeeding safety.
QYZZRS Interlock Kit For Eaton Culter Hammer Vertical Main
This interlock kit targets Eaton/Culter Hammer vertical main panels at 150/200 amps. It specifies a spacing of 2 1/4 inches between the main and branch breakers. The documentation stresses careful screw placement and pre-installation simulation to ensure proper alignment and successful operation to prevent simultaneous energization of utility and generator sources.
QYZZRS GE Vertical Main Interlock
Designed for General Electric vertical main panels, this kit requires spacing between 2 1/2 and 3 1/2 inches. The included installation notes guide screw placement and test simulations to prevent improper alignment. It also highlights the benefit of a manual transfer switch-like behavior to backfeed safely and keep appliances powered during outages without simultaneous generator and utility energization.
Buying Guide: Key Purchase Considerations
When choosing a generator interlock kit, consider panel compatibility first. Verify your panel brand and model, whether it’s Square D QO/Homeline, Eaton BR/CH, Siemens/Murray, or GE vertical mains. Confirm the exact spacing required between the main and generator or branch breakers. Incorrect spacing can render the kit ineffective or unsafe.
Next, evaluate installation complexity. Some kits come with alignment aids, drilling guides, and screws that facilitate mounting. Others emphasize a test-run simulation before final mounting to reduce the risk of misalignment and backfeed issues. If you’re not confident in handling panel work, consulting a licensed electrician is advisable.
Safety features and code compliance are critical. A properly installed interlock prevents backfeeding into the utility grid, reduces electrical shock risk, and helps comply with local electrical codes. Look for kits that explicitly address main-off and generator-on positions and ensure the interlock fully blocks simultaneous energization of both sources when needed.
Price and availability vary by brand and model. While not listing prices here, compare kits based on material quality (steel construction, finish), warranty terms, and included installation aids. Reading user reviews about ease of installation and long-term reliability can provide practical insights beyond specifications.
Finally, plan for future maintenance. Some interlock kits are easier to remove and reinstall if you upgrade panels or generators. Check whether you’ll need any additional adapters or spacers for future configurations, and ensure you can source replacement parts if needed.
In summary, choose an interlock kit that matches your panel, provides clear spacing guidance, and offers straightforward installation steps with safety-focused operation. A properly selected kit helps maintain continuous power during outages while protecting your electrical system and utility personnel.