Wiring Device Manufacturing: ABB Robots on the Line

Light switches, wall sockets, lamp holders and the small breakers in the fuse box get little attention until one fails. Wiring device manufacturing turns brass, copper, springs and moulded plastic into millions of these parts, each one expected to work for decades behind a wall. This post traces wiring device manufacturing from Edison's screw socket and Harvey Hubbell's plug to Bakelite switches and the first miniature circuit breakers, then looks at the robot lines building switches today, including an ABB plant in Finland, and at what comes next for factories and for the homes these devices go into.

A modern Schuko wall socket module, the kind of wiring device made by the million. Photo: Retired electrician / Wikimedia Commons (CC0)

From Edison's screw socket to Bakelite switches

Thomas Edison's screw base for light bulbs was patented in 1881; he is said to have copied the lid of a kerosene can. By about 1908 it was the most common lamp base in the United States. The plug came later. Harvey Hubbell, who founded his company in Bridgeport, Connecticut, in 1888, patented a pull chain lamp socket in 1896 and the separable attachment plug, US patent 774,250, in 1904. In 1916 he patented a three blade plug with a ground pin. Brass lamp holders built around Edison's thread, like the old Leviton socket pictured below, still turn up in old lamps.

An old Leviton brass lamp socket with a turn knob, built around Edison's screw thread. Photo: Retro00064 / Wikimedia Commons (CC BY-SA 3.0)

Plastic changed the work. Leo Baekeland developed Bakelite in Yonkers, New York, in 1907, and its first commercial electrical use, in 1908, was moulding small insulating bushings for the Weston Electrical Instrument Corporation. Phenolic resin was pressed with a filler under heat and pressure, cured in a few minutes and could come out of the mould while still hot. Lamp sockets, switches and plugs moved to moulded housings that needed little polishing, and a factory could copy the same part millions of times. Phenolics are still used in plugs and switches today.

The back of an old round Bakelite light switch, with its moulded base and screw terminals. Photo: Langläufer22 / Wikimedia Commons (CC BY-SA 4.0)

The breaker in the fuse box has a European start. In 1924 Brown, Boveri & Cie, one of the companies that later formed ABB, patented a miniature circuit breaker credited to engineer Hugo Stotz, who had sold his firm to BBC. It became the forerunner of the thermal magnetic breakers in home panels now. In Germany, Busch-Jaeger, founded by the Jaeger brothers in Lüdenscheid in 1879, made switches and sockets; BBC bought its electrical division in 1969. Inside every one of these devices sit contacts, springs and screws that somebody, or later some machine, had to put together.

A mid 1960s main distribution board with its fuses, built into a wooden cabinet. Photo: Phiarc / Wikimedia Commons (CC BY-SA 4.0)

Robots on wiring device lines in 2026

On 14 October 2026 Mississippi governor Tate Reeves joined a ribbon cutting at ABB's plant in Senatobia, which marked ten years in the town with a 40 million dollar expansion. When the project was announced in 2025, ABB said it would double the site's footprint to raise output of air circuit breakers and moulded case circuit breakers, products used in data centres, factories and renewable microgrids. The plant first opened in 2016 to make moulded case breakers.

An ABB robot assembling switch parts on the JOT Automation line at ABB Smart Power in Vaasa, Finland. Photo: ABB

ABB has also shown how robots assemble switches in its own plants. At ABB Smart Power's factory in Vaasa, Finland, system integrator JOT Automation built a line of 19 cells for a new switch range. It uses 20 ABB robots, among them ten IRB 1200 arms for scanning and assembly, an IRB 1600 and an IRB 2600 for loading and unloading, and an IRB 910SC SCARA. The first section started full production in spring 2024 and builds eight different switch models without changing tools; the robots change program instead. The cells were first built and tested as virtual models in RobotStudio.

An ABB robot gripper picking a small part from a feeder on the Vaasa switch line. Photo: ABB

Most of the work on such a line is small and repetitive: feeding contacts from a bowl, pressing springs into place, driving terminal screws, checking each device and packing it. ABB's own breakers, like the S201 miniature circuit breaker sold under the old Stotz name, are the sort of product these cells handle. Housings come from injection moulding, where robots such as the ABB IRB 4400 take parts out of the press. Medium voltage gear is a heavier job, covered in our post on power grid switchgear.

An ABB S201 B16 miniature circuit breaker, a descendant of the 1924 Stotz design. Photo: VoltCrafter / Wikimedia Commons (CC BY-SA 4.0)

What comes next for switches, sockets and breakers

Variety is the main problem for the next few years. Busch-Jaeger, which became a brand of ABB AG in September 2025, lists about 6,000 products, from plain switches and sockets to dimmers, motion detectors and KNX smart home devices. Short runs of many variants are hard to automate with fixed machines, which is why the Vaasa line was built to switch models in software. Smaller ABB robots such as the IRB 1100, the single arm YuMi IRB 14050 or the GoFa cobot could fit the same kind of work on other lines, though no such project has been announced.

An ABB IRB 4400 unloads parts from an ENGEL injection moulding machine in a Spanish plant. Photo: ABB

Homes are asking more of these devices too. On 14 October 2026 Leviton announced TrueArc, an arc fault detection technology meant to cut nuisance tripping in modern homes, and smart switches and sockets now carry radios and chips as well as brass contacts. That adds electronics assembly, firmware loading and functional testing to what used to be a mechanical product. Each extra step needs a tester or a robot at the end of the line, and every device still has to pass electrical safety tests before it leaves the plant.

An ABB robot cell on the Vaasa line, where eight switch models share the same tools. Photo: ABB

Cost and skills will decide how fast the rest of the industry follows. A single switch sells for little, so a robot cell has to run for many years on many products to pay back, which is why the Vaasa line was planned for a 25 year life. Plants also need technicians who can program robots, maintain feeders and read test data, and safety rules for people working next to the cells. ABB also tied the Senatobia expansion to customers across North America upgrading ageing power infrastructure, so the demand is there.

The back of a socket module, with the brass contacts and terminals that assembly cells must fit. Photo: Retired electrician / Wikimedia Commons (CC0)

Innovation

AI solutions for effortless ABB robot control.

Automation

Robotics

ceojohntran@chatwithrobot.net

+84905311611

© 2025. All rights reserved.

qtran1215@gmail.com