Generator Cords: 30 Amp vs 50 Amp
Buy the cord that matches the biggest outlet on your generator and the inlet box on your house; the amp rating isn't something you choose separately. A 50 amp generator cord in Generac's kits is 6/4 wire with a 14-50 plug at the generator, while the 30 amp cord is 10/4 with L14-30 twist-lock ends.
The two cords side by side
| 30 amp cord | 50 amp cord | |
|---|---|---|
| Generator outlet it fits | L14-30R twist-lock | 14-50R |
| Generator end on Generac's cord | L14-30 male | NEMA 14-50 male |
| House end on Generac's cord | L14-30 female | CS6364 female |
| Inlet on the house | L14-30 | CS6377 |
| Generac's wire | 10/4 | 6/4 |
| Length in Generac's kit | 10 ft | 10 ft |
In a cord label like Generac's 10/4, the first figure is the wire gauge and the second is the number of conductors. Four conductors means two hots, a neutral and a ground, so one cord can feed both sides of your panel. Smaller gauge numbers mean thicker wire, so Generac's 6/4 cord is the heavy one.
Which one you need
Look at the generator, not the house. If its biggest outlet is an L14-30R twist-lock, you need the 30 amp cord. If it has a 14-50R outlet, the 50 amp cord gets you the full output. Generac's 30-amp 1-2 circuit switch is meant for generators starting at 5 kW, and its whole-house switch with a 50-amp generator side is for generators starting at 8 kW.
Your inlet box has to match too. A 30-amp L14-30 inlet takes a 30-amp L14-30 cord, and an adapter can't make it carry more. That's covered in generator inlet box basics.
Cord length and extension cords
The kit cords are short. Generac's bundles ship a 10-foot cord, but CPSC wants the generator at least 20 feet from doors, windows and vents. If your inlet sits near a window, buy a longer cord with the same rating and ends, not an extension cord bolted on. Every extra connection is another place for heat and water.
For plugging appliances straight into the generator, CPSC says to use heavy-duty cords made for outdoor use and to make sure each cord's wattage rating is higher than the total of everything plugged into it. An extension cord like that is fine for appliances as long as its rating covers the load, but it's never a house hookup.
Cords to avoid
- Male-to-male cords. They're sold online as "generator cords" and they're the deadliest thing in this whole category.
- Adapter stacks. An adapter changes the plug shape. It doesn't change what the wire, the inlet or the generator can carry.
- Light-duty indoor cords on a generator, and any cord that's warm, cracked or has a bent prong.
- A cord buried in snow or lying in standing water at the connection.
Generac cords and pull cords
Generac sells both 30 and 50 amp cords with its HomeLink transfer switches, and bundles with cords and inlet boxes included. Any brand works if the ends match your generator and inlet and the cord is rated for the amps.
A "pull cord" is a different part entirely. It's the recoil starter rope on a pull-start generator. Order it by your generator's model number from the maker's parts site.
FAQ
What size cord do I need for a 50 amp generator?
You need a 4-conductor cord with a 14-50 plug for the generator and a connector that matches your inlet. Generac's 50-amp cord uses 6/4 wire with a CS6364 connector at the house end. Don't go lighter than what the generator maker specifies.
Can I use a 50 amp cord for a 30 amp generator?
Not directly, because the plugs are different and a 30-amp generator has an L14-30R outlet while the 50-amp cord fits a 14-50R. An adapter makes it fit, but you still only get what the generator can deliver. Simpler to buy the matching cord.
How big of a generator do I need to run 50 amps?
Generac's whole-house manual switch with a 50-amp generator connection is listed for portable generators starting at 8 kW with a 50-amp receptacle. Size the generator to your loads first, then pick the cord that matches its outlet. Our generator sizing guide walks through the math.
Who makes the best 50 amp generator cord?
Brand matters less than the specs. Look for the right ends for your generator and inlet, the right wire gauge for the rating, and an outdoor-rated jacket. Never connect to household wiring without a transfer switch.
Sources
- GeneracHomeLink Manual Transfer Switch spec sheet (6852, 6853, 6854, 9854, 9855) (opens in a new tab)
- U.S. Consumer Product Safety CommissionPortable Generator Safety Alert (opens in a new tab)
- GeneracAbout Portable Transfer Switches (HomeLink) (opens in a new tab)
- GeneracWhole House 200A Utility / 50A Generator Manual Transfer Switch (opens in a new tab)
- Generac30-Amp 1-2 Circuit Manual Transfer Switch (opens in a new tab)
- South Carolina State FireGenerator Safety (opens in a new tab)