Molded-Case Circuit Breakers 3 Molded-Case Circuit Breakers Molded-Case Circuit Breakers Family 1 Product Description, History, Major Product Introduction V12-T3-2 General Information . V12-T3-3 2 Nameplate Data . V12-T3-3 Identifying Factory Original Circuit Breakers . V12-T3-4 3 Replacement and Upgrade Options V12-T3-5 Replacement Guides 4 Miniature Circuit Breakers . V12-T3-6 Molded-Case Circuit Breakers V12-T3-10 5 Replacement Devices Circuit Breakers . V12-T3-15 6 Molded-Case Switches V12-T3-61 Motor Circuit Protectors . V12-T3-63 7 Accessories V12-T3-63 Panelboard Replacement Breakers . V12-T3-80 8 Replacement Guide V12-T3-81 Motor Control Center Replacement Breakers V12-T3-88 9 Technology Upgrades for Circuit Breakers V12-T3-91 Handle Mechanisms V12-T3-95 10 Replacement and Service Capabilities V12-T3-112 Cross-Reference 11 Westinghouse, Challenger and Bryant Replacements V12-T3-113 Breaker Replacements V12-T3-115 12 Mining Breaker Replacements V12-T3-162 Pricing Information . V12-T3-168 13 14 15 16 17 18 19 20 21 22 23 24 25 Volume 12Aftermarket, Renewal Parts and Life Extension Solutions CA08100014EOctober 2016 www.eaton.com V12-T3-1Molded-Case Circuit Breakers 3 attempted to find a solution 1923 when the modified arc Product History Molded-Case 1 to the problem. Meetings extinguisher was coupled Circuit Breakers Originally a with switch manufacturers with a thermal tripping Westinghouse Product were initiated in an effort mechanism. It was not until The need for molded-case 2 to find a solution. Switch four years later, however, circuit breakers came about manufacturers were asked to that Westinghouse research in 1918 when numerous develop a switching device engineers found the ideal applications for electrical 3 that would interrupt a circuit combination of materials and motors resulted in a demand under prolonged overload design that permitted circuit for a device that would conditions. The device would breakers to interrupt fault 4 ensure safe operation and, have to be safe, reliable and currents of 5000A at 120 Vac at the same time, protect Molded-Case Circuit Breaker Family tamperproof. It should also or Vdc. One year later, electrical circuits. be resettable so as to be Westinghouse placed the 5 Product Description reusable after an interruption first circuit breaker on the During this period, individual Eatons molded-case circuit without replacing any parts. market. Its acceptance motors were used for the breakers are designed to 6 This search for better circuit was instantaneous. first time in industrial plants provide circuit protection protection resulted in many to operate machine tools and for low voltage distribution Since that initial introduction different but unacceptable in private homes to operate 7 systems. They are described in 1927, Westinghouse approaches to the problem. appliances. Plant electricians by NEMA as ...a device continued to be at the forefront These early meetings and were constantly changing for closing and interrupting of circuit breaker technology subsequent efforts prepared fuses blown during motor 8 a circuit between separable with an unprecedented series the groundwork for the startups because of the lack contacts under both normal of circuit protective eventual development of the of properly designed fuses for and abnormal conditions, enhancements and 9 molded-case circuit breaker. motor circuit protection. and furthermore as ...a introductions as chronicled Homes experienced similar breaker assembled as an After intensive research and below. In 1994, Eaton, another problems when electrical integral unit in supporting development, Westinghouse world-class technology leader, 10 circuits were overloaded. an enclosed housing of produced the DE-ION arc acquired the Westinghouse Inspectors were concerned insulating material. The extinguisher for use in large Distribution and Control about fire hazards because of 11 NEC describes them as oil circuit breakers. Although Business Unit (DCBU) plug fuses being bridged with . a device designed to too large in its initial form to and integrated it with their pennies and the installation open and close a circuit by be practical for small circuit Cutler-Hammer business of fuses with too high an 12 non-automatic means, and to breakers, the arc extinguisher unit forming a powerful, new ampere rating. open the circuit automatically was eventually modified combination, poised to meet on a predetermined overload into a usable size. The first the challenges of the next Inspection authorities 13 of current, without injury to compact, workable circuit 100 years. became involved and itself when properly applied breaker was developed in within its rating. 14 Circuit breakers protect Time LineMajor Product Introductions against overloads in 15 Year Product 1920 1930 1940 1950 1960 1970 1980 1990 1995 2000 2002 Present conductors and protects 1923 First compact, workable circuit breaker developed by Westinghouse against short circuits in 1927 Westinghouse introduced the first complete circuit breaker line, connected apparatus such as 16 rated 10 600A, 600V motors and motor starters. 1939 Along with ordering information and style numbers, the various maximum current ratings came to be known by frame designations: Circuit breakers are designed 17 50A E-Frame for use in panelboards, 100A F-Frame (non-interchangeable trip) 100A G-Frame switchboards, motor control 225A K-Frame 600A L-Frame 18 centers, control panels, 1970 Motor Circuit Protector (MCP) introducedfirst sensitive, low combination starters, level protection designed specifically for motor circuits individual enclosures and 1973 SELTRONIC introducedfirst molded-case circuit breaker 19 bus duct plug-in units. with an electronic trip unit 1979 Current Limit-R circuit breaker introduced first true current limiting trip unit 20 1982 Series C Family introducednew world-class standard, meeting increasing interrupting requirements without sacrificing compact size 1994 Westinghouse Distribution and Control Business Unit (DCBU) acquired by Eaton, integrated with Cutler-Hammer 21 (the Cutler-Hammer line of molded case circuit breakers was sold when merged with Westinghouse) 1995 OPTIM Family introducedfirst truly programmable molded-case circuit breaker 22 2002 Next Generation E125, J250 2004 Series G First Global Breaker Line 23 24 25 V12-T3-2 Volume 12Aftermarket, Renewal Parts and Life Extension Solutions CA08100014EOctober 2016 www.eaton.com