Answering the need for safe, code-friendly backfeed control, this guide reviews top panel interlock kits designed for generators. Best for homeowners seeking reliable, code-compliant backup power, these kits prevent simultaneous main and generator power. The table below highlights five strong picks across popular panels, helping you choose based on compatibility, spacing, and installation considerations. The products below are chosen for clear installation steps, documented compatibility, and practical safety benefits during outages.
| Product | Panel Compatibility | Spacing (inches) | Why It Stands Out |
|---|---|---|---|
| Natupal Generator Interlock Kit (SD200A) | Square D QO or Homeline 150/200 A | 1 3/8 | Strong safety direction of power with clear installer guidance |
| EXCELFU BR Series Interlock Kit | Eaton/Cutler Hammer BR, CH series 150/200 A | 1 1/4 – 1 7/16 | Flexible spacing and clear safety features |
| SPZOCE GE 150/200 A Interlock Kit | General Electric GE 150/200 A | 1 1/4 | Easy drill and installation with safety focus |
| EXCELFU GE 150/200 A Interlock Kit | GE 150/200 A Panels | 1 1/4 | Consistent safety mechanism for GE panels |
| XMK Siemens/Murray 150/200 A Interlock Kit | Siemens or Murray 150/200 A | 7/8 – 1 1/4 | Versatile spacing options for plug-on-neutral and traditional panels |
Natupal Generator Interlock Kit for Square D QO or Homeline
Best for homeowners with Square D QO or Homeline panels who want a straightforward, professional interlock. The kit offers a 1 3/8 inch spacing between the main and generator breakers, providing a direct path to safely backfeed while keeping the main supply protected. The package emphasizes compatibility with 150/200 amp configurations and emphasizes safety—reducing the risk of backfeed during outages.
Who it’s best for: Homeowners with Square D panels needing a robust, simple installation that clearly directs generator power to selected circuits. Why selected: clear spacing specification, strong safety framing, and established compatibility with common Square D panels.
Caution: Verify exact panel model and existing breaker layout before purchase to ensure proper alignment with the 1 3/8 inch spacing requirement.
EXCELFU Generator Interlock Kit for BR Series
Better for Eaton Cutler Hammer BR and CH series panels at 150/200 amp, this interlock kit provides a safe, backfeed solution to keep essential loads running during outages. It specifies a 1 1/4 inch to 1 7/16 inch spacing between main and branch breakers, offering flexibility for varied BR panel configurations. The kit is designed to prevent simultaneous energization from mains and generator, improving reliability during emergencies.
Who it’s best for: Homeowners with Eaton BR/CH panels seeking a cost-effective, dependable interlock. Why selected: broad compatibility within BR/CH families and practical spacing range.
Caution: Installation notes recommend verifying the exact model and neutral configuration to ensure correct alignment of the interlock plate with the panel interior.
SPZOCE GE 150/200 Amp Interlock Kit
Geared toward General Electric GE panels, this 1 1/4 inch spacing model aims to simplify safe generator connection during outages. It emphasizes safe directing of generator power to chosen circuits while ensuring all household appliances remain usable. The kit includes installation hardware and a drill bit for straightforward mounting.
Who it’s best for: GE panel owners who want a practical, industry-standard interlock solution. Why selected: clear compatibility note, inclusion of installation tools, and a focus on safe operation.
Caution: Confirm the panel’s exact GE rating and spacing to avoid misalignment during installation.
EXCELFU GE 150/200 Amp Interlock Kit
This GE-compatible interlock kit focuses on safe, reliable backfeeding for GE panels in 150 and 200 amp configurations. The main breaker and branch breaker spacing is fixed at 1 1/4 inch, with emphasis on a safe, simultaneous-safe operation to prevent backfeed hazards. It’s a practical choice for households aiming for predictable performance inside GE panels.
Who it’s best for: GE panel owners requiring a dependable, standardized interlock component. Why selected: consistent spacing specification and emphasis on safe operation.
Caution: Double-check compatibility with plug-on-neutral vs. non-plug-on-neutral GE panels to ensure correct fit.
XMK Siemens/Murray 150/200 A Interlock Kit
Best for Siemens/Murray panels, this interlock kit offers a 7/8 to 1 1/4 inch spacing range between main and branch breakers, enabling flexible fitment for different panel layouts. It helps prevent simultaneous mains and generator power and directs generator power safely to selected circuits, giving households reliable backup access to essential outlets and appliances.
Who it’s best for: Homeowners with Siemens or Murray 150/200 amp panels seeking flexible spacing options. Why selected: wider spacing range accommodates diverse panel designs.
Caution: Ensure the exact model and spacing match your panel’s requirements to avoid installation issues.
Buying Guide
What is a generator interlock kit and when should I use one?
A generator interlock kit couples with your main service panel to safely connect a portable generator without backfeeding the utility line. Use one to keep mains and generator power from energizing the same circuit simultaneously, protecting both your equipment and utility workers during outages.
How do I choose the right interlock kit?
- Panel compatibility: Confirm the kit fits your panel brand and model (Square D, GE, Eaton, Siemens/Murray, etc.).
- Required spacing: Check the documented spacing between main and branch breakers (commonly 1/4 inch to 1 3/8 inches). Match your panel’s design.
- Installation practicality: Look for included installation tools and clear manuals that suit your skill level.
- Safety features: Favor kits that prevent simultaneous energization and provide straightforward generator power routing.
What installation considerations matter?
- Power needs: Ensure the generator’s capacity matches the circuits you intend to backfeed.
- Placement and clearance: Allow enough space around the panel for safe drilling and wiring.
- Electrical codes: Verify local code requirements and permit needs for generator interlock installations.
What are common limitations to expect?
- Not all kits support every GE, BR, CH, or plug-on-neutral configuration; verify exact model compatibility.
- Some spacings are fixed, while others offer a range; choose based on your panel’s interior layout.
- Installation complexity can vary; some kits require drilling and precise alignment.
How should I plan the installation steps?
- Turn off main power and confirm no circuit is live.
- Remove panel cover and locate main and branch breaker positions.
- Align interlock plate with correct spacing as per kit instructions.
- Drill or secure mounting screws as directed, then mount the interlock plate.
- Test alignment with a generator transfer procedure per the included manual.
FAQ
- What panel types do interlock kits support? They support multiple brands, including Square D, GE, Eaton, Siemens/Murray, with varying spacing specs. Always verify model compatibility.
- Do interlock kits require professional installation? Some installations are straightforward, but many require basic electrical skills; check local codes and consider a licensed electrician for safety.
- Can I backfeed a whole-house generator with an interlock kit? Interlock kits are designed for safe backfeeding specific circuits, not for backfeeding the entire home. Consult your panel capacity and generator output.
- Will an interlock kit affect my warranty? Manufacturer guidelines vary; follow the installation instructions precisely to avoid warranty issues.
- What maintenance is needed after installation? Routine checks for tightness of mounting screws and wiring connections, plus periodic visual inspections for wear or corrosion, are advisable.
- Is there a preferred brand? Preference depends on your existing panel brand and spacing needs; choose the kit that matches your panel and provides clear safety benefits.