Best Portable Generator Interlock Kit Options for Safe Home Power
Looking for a reliable portable generator interlock kit to safely backfeed your home during outages? This guide highlights five top options, each best for different panel brands and spacings. These interlock kits prevent backfeed by ensuring the main and generator breakers cannot be on at the same time, while letting you run essential appliances. Ideal buyers include do-it-yourself homeowners, electricians buying for residential installations, and anyone upgrading from a transfer switch for safer generator use. The table below summarizes the key details to compare at a glance.
| Product | Brand | Panel Compatibility | Spacing | Why It’s Notable |
|---|---|---|---|---|
| XMK Generator Interlock Kit | XMK | Siemens/Murray 150/200 Amp | 7/8″ – 1 1/4″ | |
| Natupal Interlock Kit (SD200A) | Natupal | Square D QO/Homeline 150/200 Amp | 1 3/8″ | |
| QYZZRS Interlock Kit (Square D Homeline Meter Main) | QYZZRS | Square D Homeline 150/200 Amp | 1 3/8″ | |
| LiftCharger 30 Amp Gen to House Kit | LiftCharger | Square D Homeline 150/200/225 Amp | Not specified here | |
| SPZOCE Eaton BR Interlock Kit | SPZOCE | Eaton Cutler Hammer BR 150/200 Amp | 1 1/4″ – 1 7/16″ |
XMK Interlock Kit for Siemens/Murray Panels
Designed for Siemens or Murray 150 or 200 Amp panels, this interlock kit uses a 7/8 to 1 1/4 inch spacing between the main and branch breakers. It’s a practical choice for homeowners who want a straightforward, safe way to backfeed. Best for buyers with Siemens/Murray panels seeking a compliant and simple install that protects utility workers from backfeed currents.
Best for: homeowners with Siemens or Murray panels who need a reliable, simple interlock solution. Choose this if your spacing falls within the 7/8″ to 1 1/4″ range and you want a straightforward kit without extra frills.
Caution: Verify model compatibility and spacing before purchasing to ensure fitment with your panel’s main and branch breakers.
Natupal Interlock Kit for Square D QO/Homeline
Compatible with Square D QO or Homeline 150/200 Amp panels, with 1 3/8 inch spacing between main and generator breakers. This professional interlock kit aims to safely direct generator power to designated circuits during outages. It’s a solid option for Square D owners who want a complete kit with a clear installation path.
Best for: Square D panel owners who need a well-documented installation process and reliable interlock performance. Better for users who favor 1 3/8″ spacing and a focused Square D solution.
Caution: Confirm that your exact main-to-generator spacing is 1 3/8″ prior to purchase to avoid fit issues during installation.
QYZZRS Interlock Kit for Square D Homeline Meter Main
Specifically for Square D Homeline Meter Main 150 or 200 Amp Breakers, this kit is a complete package with installation screws, drill bit, and various labels. It’s ideal for users who want a ready-to-install interlock setup and clear customer-facing documentation for safe operation during outages.
Best for: Square D Homeline meter main setups where a full accessory package aids accurate alignment and compliant operation. Use this when you prefer an all-in-one kit with setup guides.
Caution: Follow all installation notes closely to align interlock positioning correctly and avoid misalignment that could impair operation.
LiftCharger 30 Amp Generator to House Kit
Includes a 30-amp generator to house hookup with a power inlet box and a panel interlock kit. It is designed for Square D Homeline 150-225 Amp load centers and supports powering selected circuits during outages. This option is best for users seeking a 30-amp setup to backfeed essential loads without upgrading to a higher-capacity solution.
Best for: users needing a compact, affordable kit that supports smaller generator output, while still allowing selective circuit powering. Choose this if your generator is within 30 amps and you want a Plug-and-Play arrangement.
Caution: Ensure your generator’s output and your home’s load requirements align with a 30-amp kit to avoid underpowering critical circuits.
SPZOCE Eaton BR Interlock Kit
Compatible with Eaton Cutler Hammer BR Series 150/200 Amp panels, with spacing between main and branch breaker at 1 1/4″ to 1 7/16″. The kit includes installation hardware and is designed to prevent backfeed while letting you run household appliances safely.
Best for: Eaton BR panel owners who need a robust interlock solution with precise spacing guidance. Better for applications requiring strict NEC compliance for backfeeding safety.
Caution: Verify the exact spacing on your panel to ensure the kit will fit as described, since spacing varies slightly among BR models.
Buying Guide: Interlock Kits for Portable Generators
Key considerations help buyers pick the right interlock kit for their panel and home backup needs.
- Panel compatibility: Confirm the kit’s listed panel brands and amperage (150/200 Amp are common). Mismatches can render the kit unsafe or unusable.
- Spacer spacing: Interlock kits rely on precise main-to-generator breaker spacing. Measure your panel’s spacing before purchasing (examples include 7/8″, 1 1/4″, 1 3/8″).
- Ease of installation: Look for kits that include installation hardware, drill bits, and clear instructions. Missing components can delay setup or create errors.
- Safety compliance: Choose kits designed to prevent simultaneous operation of mains and generator power, reducing backfeed risk and protecting utility workers.
- Included accessories: Some kits come with cords, inlets, labels, and test procedures. These can simplify commissioning and daily operation.
- Future-proofing: If planning panel upgrades, consider modular options that support new spacings or panel types.
Practical installation tips
- Read the installation bulletin fully before starting to avoid misalignment.
- Use a levels and a squared frame to position the interlock plate accurately relative to the main breaker.
- Test the interlock in a staged process to confirm it prevents both breakers from engaging at the same time.
Frequently Asked Questions
- What is an interlock kit for generators? It is a device that prevents simultaneous connection of the main power and a generator, allowing safe backfeeding to selected circuits.
- Do interlock kits require professional installation? Many are designed for DIY installation, but following local code requirements is essential. Consider professional help if unsure.
- Can I use an interlock kit with any generator size? Interlocks are dimensioned to panel spacing and amperage; ensure your generator’s output aligns with the kit’s capacity.
- Is backfeeding safe for utility workers? Yes, when installed correctly, interlock kits prevent backfeed and reduce risks to workers during outages.
- What spacing options are common? Common spacings include 7/8″, 1 1/4″, and 1 3/8″ between main and generator breakers.
- Do interlock kits include all installation hardware? Many kits include screws, drill bits, and labels; verify the package contents before purchase.