Best Generator Interlock Switch Kit for Safe Home Backup Power
Power reliability matters, especially during outages. Generator interlock kits allow you to safely backfeed a portable generator into your home’s electrical system without backfeeding the utility. This article highlights five top interlock kits compatible with common panel brands and models, explaining what to consider before buying and how each kit supports safe, code-compliant operation.
Overview of selected products:
| Product | Brand | Panel Compatibility | Spacing (inches) | Key Benefit |
|---|---|---|---|---|
| Natupal Generator Interlock Kit SD200A | Natupal | Square D QO/ Homeline 150/200 A | 1 3/8 | Directs generator power safely with reliable spacing |
| Generator Interlock Kit for Eaton BR Series | QYZZRS | Eaton BR/CH 150–200 A | 1 1/4 – 1 7/16 | Flexible spacing for BR and CH panels |
| Square D QO/Homeline Interlock Kit | QYZZRS | Square D QO/Homeline 150/200 A | 1 3/8 | Professional-grade interlock kit for popular Square D panels |
| EXCELFU BR Series Interlock Kit | EXCELFU | Eaton Cutler Hammer BR 150/200 A | 1 1/4 – 1 7/16 | Safe backfeeding with reliable installation notes |
| GE Vertical Main Interlock Kit | QYZZRS | General Electric vertical main 150/200 A | 2 1/2 – 3 1/2 | Wide spacing for GE vertical main panels |
Natupal Interlock Kit SD200A For Square D Panels
- Compatible Models: Square D QO or Homeline 150/200 amp panels.
- Spacing: 1 3/8 inches between the main and generator breaker.
- Safety-focused design to safely backfeed a generator and keep essential appliances running during outages.
QYZZRS Interlock Kit For Eaton BR/CH Panels
- Compatible Models: Eaton Cutler Hammer BR and CH Series 150/200 A panels.
- Spacing: 1 1/4 to 1 7/16 inches between main and generator breaker.
- Includes installation notes to align screws and test positioning for proper operation.
QYZZRS Interlock Kit For Square D QO/Homeline
- Compatible Models: Square D QO and Homeline 150/200 amp panels.
- Spacing: 1 3/8 inches between main and generator breaker.
- Notes emphasize installation steps, including screwing in place before alignment checks.
EXCELFU BR Series Interlock Kit
- Safe backfeeding: Provides a cost-effective, safe way to power essential loads via portable generator.
- Spacing: 1 1/4 to 1 7/16 inches between main and branch breakers.
- Compatibility: BR Series panels from Eaton/Cutler Hammer; includes installation guidance.
GE Vertical Main Interlock Kit For 150/200 A
- Compatible Models: General Electric vertical main 150/200 amp panels.
- Spacing: 2 1/2 to 3 1/2 inches between main and branch breakers.
- Installation notes stress proper screw attachment and alignment checks prior to use.
Siemens/Murray Interlock Kit 150/200 A
- Compatible Models: Siemens/Murray 150 or 200 amp panels.
- Spacing: 7/8 to 1 1/4 inches between main and branch breakers.
- Designed to prevent simultaneous ON states for mains and generator power, reducing risk during outages.
WHXMHRQ Interlock Kit For Square D QO/Homeline
- Spacing: 1 3/8 inches between main and generator breaker.
- Compatibility: Square D QO and Homeline 150/200 amp panels.
- Notes cover alignment, drilling, and screws placement to ensure correct operation.
Buying Guide: Key Factors To Consider
- Panel compatibility: Confirm the interlock kit supports your panel brand and model (Square D QO/Homeline, Eaton BR/CH, GE vertical, Siemens/Murray, etc.).
- Spacing requirements: Match the exact spacing between main and generator breakers to ensure reliable operation and safe backfeeding.
- Installation prerequisites: Some kits require pre-attached screws, provided drill bits, or simulated alignment before final mounting. Follow manufacturer steps carefully.
- Safety and compliance: An interlock kit should prevent simultaneous energization of utility and generator sources. Check that the kit aligns with local electrical codes and utility requirements.
- Material and build: Look for sturdy steel construction and corrosion resistance for long-term reliability in residential environments.
- Installation impact: Assess whether professional installation is advisable, especially for complex panel configurations or older systems.
- Maintenance and documentation: Keep installation instructions and warranty information accessible for future panel servicing or expansions.
- Cost vs benefit: Weigh the upfront kit cost against the safety risk reduction and power availability during outages.