IEEE 3004.5-2014 pdf free
IEEE 3004.5-2014 pdf free.IEEE Recommended Practice for the Application of Low-Voltage Circuit Breakers in Industrial and Commercial Power Systems.
Because of the VCT large number of MCCBs which arc produced for a peat saricty of appbcanons. several sub4ypes of MCCBs arc widely recognized within the industry Two of the more popular sub-types of MCCBs are insulated-case circuit breakers (ICCBs) and miniature circuit breakers (MCBs) Thcsc arc discussed in more dctail below, but it should be noted that because these types arc not separately defined within UI 489. the disnngwshing characteristics described arc usual and commonly provided within the market, but are not gLiarantccd and may vary from one brand to another
The t types of MC(Bs arc as follows:
a) Miniature circuit breakers
b) Insulated-case circuit breakers
Each one of these circuit breakers has different design charactcnshcs and. in many cases. dil1rvnt appLication requirements.
NOT1 UI 1077 dcfincs des ices called supplenicntuy paIcctor which pro sorrir circuit breaker-like funclioni but e nut circuit breakers within the contest oF applicable North Ainencai standards and hence are used to wppknicn other osercurrent protection within the guidelines prescribed by the National Hectrical Code-a (NECa) MPA 70. and IL 1077 This 11:1+ recomnicndcd practice duct not cot-u supplementary lwutcctun
M(’CHs, as a claus, arc tested and rated in aecordaswc with UI. 489 Their current-carrying parts. mei.hanisms. and tnp devices arc compklcl) cont.ained within a molded case of insulating material. MCC’Bs arc available in the widcst range of sizes, from the smallest (15 A or less) to the largest t(N)O A). and with various interrupting ratings for each frame size. They are charactcn,cd generally by fast interruption short-circuit elcnients Virtually all MCCBs interrupt fast enough to limit the amount of prospective fault current let-through. and some limit enough current and operate fast enough to be identified as cuncig-lim.ting circuit breakers. The smaller continuous-current ratings arc equipped with thermal-magnetic or magrectic-enly trip units, larger sues arc also available with thcnnal-magnctw or electronic trip units. With electronic trip units, they can base limited shan-deby and ground-fault sensing capability. The cover and base of smaller M(’CBs are designed so that the %K’CBs cannot be opened for maintenance purposcs The main contacts of MC’CBs cannot be removed; howescr, some MC’CBs arc available with internal Iicld-installabk accessories. M(’CBs arc available in stationary or plug-in construction with circuit breaker enclosures that can he flush or surface mounted.
rét)ini the M(CB classification there is another group of dc’ ices that is known within the industry as M(’Hs. The term miniature circuit breaker is notable because it is used to describe circuit breakers that arc typically I in (25.4 mm or less wide per pole and arc commonly used in residential or lighting circuit applications at 120 V. 208 V. arid 240 V. This type of circuit breaker oPtcn is provided with integral electronic ground fault or arc fault protection in addition to the thermal magnetic overcurrcnl protection. M(Hs do not hasc a separate or unique designation within the UI. 489 standard, and generally are tested as M(’CBs per UI 489 requirements.IEEE 3004.5 pdf free download.
