Half a century of power interconnection

In honour of the golden anniversary of the Type SB connector, this article looks back at some of the product inventions and innovations produced by APP over the last 50 years.

1953 was quite a year for innovators and pioneers.

Cambridge University research fellow, James Watson, and a graduate student at that same school, Frances Crick, helped to solve the mystery of what we humans are made of with their published discovery of the structure of DNA.

Novelists, Ray Bradbury and Arthur C.

Clarke, both published ground-breaking, best-selling sci-fi novels.

Sir Edmund Hillary and Tensing Norgay accomplished something straight out of sci-fi and adventure fiction, scaling Mount Everest on foot.

And that same year, 1953, an inventor by the name of Edward D "Don" Winkler, working for Albert and JM Anderson Mfg Co, filed a patent for the first storage battery connector (SBR-2).

And while some might say that this is not on the same scale as hiking Mount Everest or discovering DNA, variations on this pioneering little two-piece device have empowered everything from forklifts to wheelchairs to golf carts.

It has evolved numerous times and been imitated even more.

Even today, companies are still "introducing" their own, often inferior, versions of Winkler's invention from 50 years ago.

In honour of the golden anniversary of the Type SB connector, this article looks back at some of the product inventions and innovations produced by the company now known as Anderson Power Products (APP) over the last 50 years.

In so doing, we'll get a sense of how APP has kept ahead of the curve, increasing power and adapting to better modes of power delivery, with connector technology continuing to accelerate even today.

Recognised today as an industry leader in the development of high quality, low cost, power interconnect solutions, APP's origins can be found in the mining and railway industries.

It all began in 1877 with the company converting an old brewery in downtown Boston into a foundry.

One of the first projects was to cast various parts for the Boston Trolley Transit System.

Product development and inventions such as the trolley pole, invented by Johan M Anderson in 1890, put APP on the map.

The trolley pole was used in the overhead system of electric railways, and provided a simple compact, efficient and durable supporting mechanism.

APP's Anderson brothers received multiple awards for their innovative trolley and railway designs.

APP's product innovations have always been driven by customer demand.

This is exemplified in the introduction and evolution of the company's two primary product lines - storage battery connectors and power pole connectors.

The introduction of the SB-2 in 1953 saw its roots in a request from industrial forklift manufacturers for a more robust connection.

What follows are some actual notes from a meeting between Anderson Mfg and Lewis-Shepard Co, an industrial truck manufacturer.

"This meeting was called at the request of Mr Hastings who was not satisfied with any of the available plugs and receptacles sold to the industrial truck field today".

"It is thought that a plug and receptacle manufacturer should study this problem with the idea of incorporating the latest materials available".

"He feels that the outer shell or jacket of the plugs and receptacles should be made of the latest type plastics of high impact value".

"Another feature desired is ease of disconnect".

"The reason for this is that occasionally it has been found necessary for the operator to pull the plug in order to stop the truck because the connector failed to operate".

"It is their suggestion that we should probably design a plug and receptacle which would cover all of the requirements of the small material handling trucks up to and including 400-pound capacity trucks".

Notes from a meeting that took place a few months later say: "Mr Hastings gave us a list of 12 features which he feels a new plug and receptacle should have".

A surprisingly short time after that, Don Winkler and Anderson Power had addressed the needs of Hastings and the forklift industry, and were applying for their patent for the Type SB connector, which was recognised by Underwriters' Laboratories on 3rd January 1954.

The original design of the SB-2 was rated at 600V and 150A and used a two-piece plasticon housing with stainless-steel springs and brass, solderable contacts.

Early users of the Type SB included Lewis-Shepard as well as Clark Equipment Co, and a close working relationship with both of these companies led to numerous product enhancements in the early to mid-1950s.

These included changes in the product housing to increased strength to improvements in the cable clamp.

APP's storage battery connector saw a number of different iterations in the 1950s and 1960s, including the single piece design SB50 which featured the extra-high heat resistance of General Electric's Lexan material, the single-piece SB350 with four different voltage keys, and the SB175 with contacts that were now made of pure copper (replacing brass contacts).

During this period, the SB connector had gained wide acceptance in the lift truck industry and had for all intents and purposes replaced spring-loaded contact button technology and pin/socket contact technologies.

Over the last three-plus decades, customer-driven improvements to the storage battery connector have been arriving at an ever-increasing rate.

Along with discos and bell-bottoms in the 1970s came APP's SBX family (SBX175, SBX350 etc) which added fail-safe features like finger-proof protection, and auxiliary contacts which automatically turned chargers off when the connector is disconnected.

In the early 1980s, APP's new wave of connectors addressed the needs of our friends across the pond.

The company developed the SBE family (SBE80, SBE160, SBE320 etc) with finger-proofing to meet European Norm EN1175-1, plus auxiliary contact.

This series is used extensively in Europe on 80V forklifts.

In the mid 1990s, APP developed the SBO320, which has grounding for 125V AC and 100A disconnect under load for daisychaining uninterruptible power supply (UPS) systems.

Around this time, a number of UPS manufacturers had already adopted the SB50, which was also being used in various applications such as golf carts, wheelchairs and scooters.

And in 2002, APP added the SB120 with low insertion force/extraction force contact for UPS systems.

That same year, the company introduced the SBE700, specifically designed for fast charging and "opportunity charging" applications which exceed the SBE320 level of current.

Bethlehem Steel recently installed these genderless, hot-pluggable SBE700's into its sixty-thousand-pound coil tractors, greatly reducing the tractors' downtime.

And just within the last year, APP released an SBS50 for UPS batteries ranging from 96 to 192V.

Meanwhile, back in the mid-1960s, Anderson Power Products answered the call of the Bay Area Rapid Transit (BART) in San Francisco, California, with the invention and introduction of the company's second major line of products, the Powerpole family of connectors.

Featuring a flat wiping contact system, an interchangeable genderless design, silver plated contacts, and modular designs, APP had UL Safety Agency approval on the Powerpole by 1964.

Powerpole connectors (PP15/45 and PP75) were first used aboard BART trains, and are still making the connection on these trains today.

In the early 1970s, APP and the Powerpole entered the office furniture and equipment market.

The PP15/45 was used by such manufacturers of office furniture as Steel Case, Hayworth and Herman Miller, and is still used today by several manufacturers of customised office wiring.

The operating voltages for this connector are 120 to 208V AC in a number of applications, and 30A per pole on 10AWG copper cable.

The Powerpoles also found their way into wheelchairs, floor sweepers and power supplies during this decade.

There arose many new markets and applications for the Powerpole in the 1990s, including rack and panel applications in UPS systems, micro-wireless telecomms equipment, and medical applications.

There were also a number of product enhancements, as the Powerpole, like its SB sibling, continued to evolve.

For example, in the mid-1990s, APP developed a touch safety/finger-proof Powerpole for high-voltage DC applications.

Also, for higher temperatures, APP added a Powerpole with a higher heat deflection plastic.

APP has built tens of millions of SB connectors since the 1950s and hundreds of millions of Powerpole connectors since the 1960s, and the company continues to add new products to both its SB and Powerpole product families.

Today APP has greater throughput than ever before, and is developing more products geared toward specific unique market segments.

According to APP's Director of Marketing, Brian Davies: "In the future, I see us continuing our tradition of focusing on customer needs, while making more products designed specifically for unique customer applications, such as smaller 100A DC power connectors for electronic systems, and more robust connectors for industrial systems and environmental protection systems".

The company recently expanded its manufacturing capabilities with two plants in Asia, and Davies sees increased global expansion in the future.

He says: "By expanding internationally and deploying development partners in different parts of the world like Asia, we will be much better equipped to service those global markets".

"Our international customers will benefit from localised engineering, design, product development and manufacturing, and logistics support".

"And we will benefit from closer contact with a vast international customer base and will be better equipped to understand and address their changing needs".

Fifty years after the invention of the SB connector by Don Winkler, Anderson Power Products continues to reign as the premiere innovator in the evolving world of power connectors, staying a few steps ahead of both the curve and the competition.

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