Generator Interlock Kit for Westinghouse Panels

Two different "Westinghouse interlock" searches

People typing this in usually mean one of two things, and they need different answers.

1. You have an old Westinghouse breaker panel. You need a kit made for that exact panel. This page is mostly about you.
2. You have a Westinghouse generator, or you saw a Westinghouse-branded kit. The Westinghouse name now shows up on generators and on the WLock line of interlock kits, and those kits are built for other brands' panels, not old Westinghouse ones. Match the kit to your panel brand, not to your generator brand.

Who makes parts for Westinghouse panels now

On January 31, 1994, Eaton bought Westinghouse's Distribution and Control Business Unit and folded it into its new Cutler-Hammer unit. That's why an electrician looking at a Westinghouse panel will usually reach for an Eaton or Cutler-Hammer catalog first.

That history doesn't guarantee a fit. Eaton's interlock instructions list specific load center catalog numbers, and the bulletin we checked doesn't mention Westinghouse-labeled panels at all. So the label decides, not the logo.

Step one: read the panel label

Open the panel door and find the label on the inside of the door or the deadfront. Write down or photograph:

• The catalog or model number (Eaton BR panels read like BR2024B125).
• The breaker type printed on the handles.
• The main breaker size in amps.
• The gap between the main breaker and the first branch breakers, since some kits are built around a fixed spacing.

If the label is gone or unreadable, stop there. An electrician can identify the panel, but nobody should buy a kit by guessing.

Eaton Type BR kits that may fit

If your label carries a Type BR catalog number, these are the factory kits to check.

Each kit ships with the interlock assembly, a hold-down kit for the back-fed breaker, new labels and screws. Eaton says the listed load centers already have the drill points or pilot holes for it. If your number isn't on the instruction sheet's list, the kit isn't listed for your panel.

The Westinghouse WLock kits

Westinghouse sells its own interlock brackets, and the naming trips people up.

Neither one is sold for old Westinghouse-labeled panels. The WLock E model list is all Eaton BR numbers. Westinghouse also recommends professional installation for code compliance.

When there's no kit for your panel

This happens a lot with older panels. Your realistic options:

• A manual transfer switch. It mounts next to the panel and powers a set of circuits you pick ahead of time, so it doesn't depend on the panel having a kit. Our interlock kit vs transfer switch page compares the two.
• A new panel. If the panel is old, full, or short on parts, an electrician may price a replacement that takes a listed kit. That's a bigger job, but it fixes two problems at once.

Skip any bracket that "fits most panels" and isn't listed for yours. An inspector checks the install against the kit's instructions and listing.

The rest of the hookup

The kit only locks out the main. You'll also need a two-pole back-fed breaker held down by the retainer, an outdoor power inlet box, and a generator cord. Champion notes inlets come in 30-amp and 50-amp versions to match the generator's L14-30 or 14-50 outlet. See generator interlock kits for every panel brand for how the pieces go together.

What it costs

Consumer Reports, as republished by the Village of Vernon Hills, puts an interlock kit at $50 to $150 plus $400 to $800 for the electrician. A transfer switch ran $500 to $1,500 installed in the same piece. Your local price depends on the panel, the inlet location and the permit.