Bus plugs for sale, Square D, Eaton, Siemens and GE busway plugs

Types of bus plug

A fusible plug holds a fused disconnect switch and accepts a fuse class such as H, K, J or R, depending on the model. A circuit breaker plug holds a molded case breaker. Siemens lists its Sentron plugs as circuit breaker, fusible and surge protective types. Square D also lists reject clips on some fusible plugs so only Class R fuses fit.

Plugs also differ by voltage, 3 pole or 4 pole, and whether they carry a ground. Two plugs of the same ampere rating can be different parts, so match all of these to the busway and to the load.

Which plug fits which busway

Plugs are not interchangeable between brands. Schneider Electric states in its own FAQ that it does not offer plug in units that can be used on GE busway, and GE sells its Spectra plugs and busway as a matched system. Treat every brand as closed, and expect even the generations within one brand to differ.

Compatibility by busway line

Each row is one closed system. Pick the row that matches the busway label.

Bus plug sizes and common catalog numbers

The ratings below come from catalog listings read for this page. They show the spread of sizes, not everything a maker sells.

New, surplus and reconditioned plugs

Surplus plugs were bought and never installed. Reconditioned plugs were pulled from service, then cleaned, inspected and retested. Used plugs come as they are. Because a plug carries live current into a load, ask for the date of the last inspection, the fuse or breaker rating that is installed, and a warranty in writing. Some resellers list reconditioned plugs with a one year warranty.

Published prices

Most sellers hide bus plug prices behind a contact for price button. The few public prices we found are below, and condition and voltage differ between them, so use them only as a rough sense of scale.

Lead times

We found no published lead time for bus plugs. Stocked and surplus plugs ship once tested. A plug that is not in stock is made to order, so give us the brand, line and rating early and we will quote the real date.

Standards

Busway is listed to UL 857, and Eaton states that Pow-R-Way III meets UL 857, CSA C22.2 No. 27 and NEMA requirements. A plug also has to be listed for the busway it plugs into, which is why a brand cross swap is not allowed.

What is a bus plug

A bus plug, also called a busway plug in unit or tap box, is a fused switch or circuit breaker enclosure that plugs into an opening in busway to feed a load. The busway keeps running and the plug protects the branch.

Can a Square D bus plug go on Eaton busway

No. Plugs are made for one busway line. Schneider Electric states it does not offer plug in units for GE busway, and the same rule holds between Square D, Eaton, Siemens and GE. Confirm the busway brand and generation before buying.

What are the standard bus plug sizes

Fusible plugs in the catalogs we read start at 30 A and run through 100, 200 and 400 A, and Square D listings go to 1,200 A. Siemens breaker plugs cover 15 to 125 A on the E frame and 250 to 600 A on the L frame.

How much does a bus plug cost

Public prices are few. A re certified Eaton 100 A fusible plug lists at $679 and a new surplus Siemens ITE 100 A plug at $1,250. Larger ratings and breaker plugs cost more, and we quote by catalog number.

Are used bus plugs safe

They can be when they are inspected and tested and carry a warranty. Ask for the nameplate photo, the installed fuse or breaker rating and the test record before you pay.