AIR
CIRCUIT BREAKERS: AN EVOLUTION
The business of circuit breakers began after WWII.
Prior to that the way the world would break a circuit
was with fuses. Fuses were effective, but they were
not smart. They had to be replaced after an overload.
With the war effort, the world saw the first
reset-able fuse—the circuit breaker. All the major
manufactures in the war effort had them; the breakers
were big and heavy, mounted on large pieces of slate
(which was considered the best non-conductive material
at the time). The massive contacts would open on
overload when two small disks submerged in oil would
break apart. The principle of this early tripping
mechanism was as the oil in a dashpot would heat up ,
it would become more viscous, and eventually the two
discs submerged in this oil would break apart as the
current would go higher . Effective, but obviously
primitive for our standards today
The 1950’s saw an era where plastics became a
larger part of our everyday lives. Plastic was also
a great non conductive material, and was the
greatest change used in the circuit breakers of this
generation. The breakers became smaller and lighter.
The tripping mechanism once a dashpot submerged in
oil was now electro-mechanical unit.
Electric Control
Supplies GE, Westinghouse, Siemens-Allis, ABB, Federal
Pacific, Cutler-Hammer And ITE Circuit Breakers
The other major issue to take note
of here was that these circuit breakers were in no
shape or form interchangeable with their like products
made in 1945. All the parts were completely different.
All the buildings build prior to this period, 1955 had
the first generation of obsolete circuit breakers.
They could not get parts, spare breakers or support
from the original equipment manufacturers. They had to
buy remanufactured circuit breakers to go with their
obsolete switchgear.
Remanufacturing
And Retrofitting GE, Westinghouse, Siemens-Allis, ABB,
Federal Pacific, Cutler-Hammer And ITE Circuit
Breakers
Electric control still stocks in
inventory the first generation of circuit
breakers-this is when ed Kahn went in to business as
electric control equipment company. He supported all
those companies who could no longer get parts or
complete breakers –rubber companies, airplane
manufactures, gas company, utilities, universities,
sewage plants, and any buildings that employed over
300 people probably had circuit breakers big enough
that were not supported.
In the 1960’s –the era of
planned obsolescence, the circuit breakers looked the
same, but were not interchangeable as the prior
generation.
The 1970’s saw the beginning of the solid state
era, diodes transistors all were a larger part of
our lives, and circuit breakers, though in
functionally basically the same, now had a solid
state trip units, these new trip units would monitor
the amperage on a given circuit far more accurately
than their predecessors, they lasted longer and
required less maintenance. These breakers were still
not interchangeable with any breaker made before it.
Two-Year Warranty On
All GE, Westinghouse, Siemens-Allis, ABB, Federal
Pacific, Cutler-Hammer And ITE Circuit Breakers
1990’s-more refining of the
tripping mechanism. Any building built prior to this
period had obsolete equipment, and could not get new
parts from the original manufacturers.
2000- I can sit with the head of maintenance
at Logan air port. He can close and trip all his
circuit breakers from his PC. He can monitor each
breaker in his “grid” and print out peak running
times. In other words the evolution of the 600 volt
circuit breaker has come to the point that his
equipment now talks back to him and records data via a
central terminal.
Electric control stocks, 480 volt circuit breakers,
5kv air circuit breakers, 5kv vacuum circuit
breakers, 15kv air breakers, 15kv vacuum circuit
breakers.
