Gear · Under $30

Neutral bonding plugs

The cheapest part on this site and the one most likely to be the difference between charging and not charging.

If your generator has a floating neutral, an EV charging cable will fault out and refuse to energize. A bonding plug jumps neutral to ground inside an unused receptacle and clears it. Full explanation here — read it before buying, because which plug you need depends on which receptacle you're leaving free.

A NEMA 14-50 receptacle
A NEMA 14-50R — 240V, 50A, four slots. This is what you charge from.

Pick by the outlet you're NOT charging from

Charging fromBonding plug goes inPlug type
NEMA 14-50R (240V, 50A)The L14-30R twist-lockL14-30P
L14-30R twist-lockA 120V household outlet5-20P
Either 240V outletAny free 120V outlet5-20P
A twist-lock electrical connector
A twist-lock connector. Yours will be an L14-30; the L21-30 shown here has the same locking action and curved blades.
A NEMA 5-20 receptacle
A 120V 5-20R. If you charge from the twist-lock instead, this is where the bonding plug goes.
What I use

Factory GENMAX twist-lock bonding plug

✓ Owned and verified on my GM10500XiT

Mine shipped in the box, which is not something every manufacturer bothers with. It seats in the L14-30R and leaves the 14-50R free for the charging cable.

Check your box first. If your generator included one, you don't need to buy anything. Look for a small plug body with no cord attached.

If yours didn't include one

L14-30P neutral bonding plug

For generators with a free 30A twist-lock receptacle. Look for a molded body with a visible neutral-to-ground jumper and a rating matching your receptacle.

  • Confirm it's a bonding plug, not a blank weather cap — listings blur the two
  • Molded beats field-assembled unless you're comfortable wiring it yourself
  • Expect roughly $15–25; much cheaper is worth a second look
Check price
120V alternative

5-20P household bonding plug

If you're charging through the twist-lock and have a standard 120V outlet free, this is the simpler and cheaper option. Same job, smaller plug.

Check price

Remove it before feeding your house. With a bonding plug installed and the generator connected through a transfer switch that doesn't switch neutral, you create two parallel neutral-ground paths. That's a code violation and it can defeat GFCI protection downstream. Details →

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