断路器（英文名称：circuit-breaker，circuit breaker）是指能够关合、承载和开断正常回路条件下的电流并能关合、在规定的时间内承载和开断异常回路条件下的电流的开关装置上海梅兰电力断路器可用来分配电能，不频繁地启动异步电动机，对电源线路及电动机等实行保护，当它们发生严重的过载或者短路及欠压等故障时能自动切断电路，其功能相当于熔断器式开关与过欠热继电器等的组合。而且在分断故障电流后一般不需要变更零部件。目前，已获得了广泛的应用。 断路器按其使用范围分为高压断路器，和低压断路器，高低压界线划分比较模糊，一般将3kV以上的称为高压电器。
按极数分：有单极、二极、三极和四极等；
按安装方式分：有插入式、固定式和抽屉式等。
断路器一般由触头系统、灭弧系统、操作机构、
脱扣器、外壳等构成。
断路器的特性主要有：额定电压Ue；额定电流In；过载保护（Ir或Irth）和短路保护（Im）的脱扣电流整定范围；额定短路分断电流（工业用断路器Icu；家用断路器Icn）等。
罗克韦尔A-B UL和IEC塑壳断路器140U系列型号：
140UDEMO2 MOLDED CASE CIR BKR DEMO
140UEH1C3C16 18KA/415V 16A 3P FF MCCB
140UEH1C3C20 18KA/415V 20A 3P FF MCCB
140UEH1C3C25 18KA/415V 25A 3P FF MCCB
140UEH1C3C32 18KA/415V 32A 3P FF MCCB
140UEH1C3C40 18KA/415V 40A 3P FF MCCB
140UEH1C3C50 18KA/415V 50A 3P FF MCCB
140UEH1C3C63 18KA/415V 63A 3P FF MCCB
140UEH1C3C80 18KA/415V 80A 3P FF MCCB
140UEH1C3D10 18KA/415V100A 3P FF MCCB
140UEH1C3D12 18KA/415V125A 3P FF MCCB
140UEH1C3D16 18KA/415V160A 3P FF MCCB
140UEH1E3C20 18KA/415V 20A 3P AF MCCB
140UEH1E3C25 18KA/415V 25A 3P AF MCCB
140UEH1E3C32 18KA/415V 32A 3P AF MCCB
140UEH1E3C40 18KA/415V 40A 3P AF MCCB
140UEH1E3C50 18KA/415V 50A 3P AF MCCB
140UEH1E3C63 18KA/415V 63A 3P AF MCCB
140UEH1E3C80 18KA/415V 80A 3P AF MCCB
140UEH1E3D10 18KA/415V100A 3P AF MCCB
140UEH1E3D12 18KA/415V125A 3P AF MCCB
140UEH1E3D16 18KA/415V160A 3P AF MCCB
140UEH1E4C20 18KA/415V 20A 4PAF MCCB
140UEH1E4C25 18KA/415V 25A 4PAF MCCB
140UEH1E4C32 18KA/415V 32A 4PAF MCCB
140UEH1E4C40 18KA/415V 40A 4PAF MCCB
140UEH1E4C50 18KA/415V 50A 4PAF MCCB
140UEH1E4C63 18KA/415V 63A 4PAF MCCB
140UEH1E4C80 18KA/415V 80A 4PAF MCCB
140UEH1E4D10 18KA/415V100A 4PAF MCCB
140UEH1E4D12 18KA/415V125A 4PAF MCCB
140UEH1E4D16 18KA/415V160A 4PAF MCCB
140UEH2E3C20 25KA/415V 20A 3P AF MCCB
140UEH2E3C25 25KA/415V 25A 3P AF MCCB
140UEH2E3C32 25KA/415V 32A 3P AF MCCB
140UEH2E3C40 25KA/415V 40A 3P AF MCCB
140UEH2E3C50 25KA/415V 50A 3P AF MCCB
140UEH2E3C63 25KA/415V 63A 3P AF MCCB
140UEH2E3C80 25KA/415V 80A 3P AF MCCB
140UEH2E3D10 25KA/415V100A 3P AF MCCB
140UEH2E3D12 25KA/415V125A 3P AF MCCB
140UEH2E3D16 25KA/415V160A 3P AF MCCB
140UEH2E4C20 25KA/415V 20A 4PAF MCCB
140UEH2E4C25 25KA/415V 25A 4P AF MCCB
140UEH2E4C32 25KA/415V 32A 4PAF MCCB
140UEH2E4C40 25KA/415V 40A 4PAF MCCB
140UEH2E4C50 25KA/415V 50A 4PAF MCCB
140UEH2E4C63 25KA/415V 63A 4PAF MCCB
140UEH2E4C80 25KA/415V 80A 4PAF MCCB
140UEH2E4D10 25KA/415V100A 4PAF MCCB
140UEH2E4D12 25KA/415V125A 4PAF MCCB
140UEH2E4D16 25KA/415V160A 4P AF MCCB
140UEH2S3D16 25KA/415V160A 3P MCS
140UEH2S4D16 25KA/415V160A 4PF MCS
140UEH4E3C20 40KA/415V 20A 3P AF MCCB
140UEH4E3C25 40KA/415V 25A 3P AF MCCB
140UEH4E3C32 40KA/415V 32A 3P AF MCCB
140UEH4E3C32HB MOLDED CASE CIRCUIT BREAK
140UEH4E3C40 40KA/415V 40A 3P AF MCCB
140UEH4E3C50 40KA/415V 50A 3P AF MCCB
140UEH4E3C63 40KA/415V 63A 3P AF MCCB
140UEH4E3C80 40KA/415V 80A 3P AF MCCB
140UEH4E3D10 40KA/415V100A 3P AF MCCB
140UEH4E3D12 40KA/415V125A 3P AF MCCB
140UEH4E4C20 40KA/415V 20A 4PAF MCCB
140UEH4E4C25 40KA/415V 25A 4PAF MCCB
140UEH4E4C32 40KA/415V 32A 4PAF MCCB
140UEH4E4C40 40KA/415V 40A 4PAF MCCB
140UEH4E4C50 40KA/415V 50A 4PAF MCCB
140UEH4E4C63 40KA/415V 63A 4PAF MCCB
140UEH4E4C80 40KA/415V 80A 4PAF MCCB
140UEH4E4D10 40KA/415V100A 4PAF MCCB
140UEH4E4D12 40KA/415V125A 4PAF MCCB
140UEH7E3C20 70KA/415V 20A 3P AF MCCB
140UEH7E3C25 70KA/415V 25A 3P AF MCCB
140UEH7E3C32 70KA/415V 32A 3P AF MCCB
140UEH7E3C40 70KA/415V 40A 3P AF MCCB
140UEH7E3C50 70KA/415V 50A 3P AF MCCB
140UEH7E3C63 70KA/415V 63A 3P AF MCCB
140UEH7E3C80 70KA/415V 80A 3P AF MCCB
140UEH7E3D10 70KA/415V100A 3P AF MCCB
140UEH7E3D12 70KA/415V125A 3P AF MCCB
140UEH7E4C20 70KA/415V 20A 4PAF MCCB
140UEH7E4C25 70KA/415V 25A 4PAF MCCB
140UEH7E4C32 70KA/415V 32A 4PAF MCCB
140UEH7E4C40 70KA/415V 40A 4PAF MCCB
140UEH7E4C50 70KA/415V 50A 4PAF MCCB
140UEH7E4C63 70KA/415V 63A 4PAF MCCB
140UEH7E4C80 70KA/415V 80A 4PAF MCCB
140UEH7E4D10 70KA/415V100A 4PAF MCCB
140UEH7E4D12 70KA/415V125A 4PAF MCCB
140UEJ0X3 100KA/415V,3P FRAME
140UEJ0X4 100KA/415V, 4P FC FRAME
140UEJ2F3D16 35KA/480V,15A 2P FF MCCB
140UEJ2G3D10 MOLDED CASE CIRCUIT BREAK
140UEJ2G3D16 MOLDED CASE CIRCUIT BREAK
140UEJ2X3 25KA/415V,3P FRAME
140UEJ2X4 25KA/415V, 4P FRAME
140UEJ4F3C80 MOLDED CASE CIRCUIT BREAK
140UEJ4X3 40KA/415V,3P FRAME
140UEJ4X4 40KA/415V, 4P FRAME
140UEJ7F3D16 MOLDED CASE CIRCUIT BREAK
140UEJ7F3D20 MOLDED CASE CIRCUIT BREAK
140UEJ7F3D25 MOLDED CASE CIRCUIT BREAK
140UEJ7S3D25 70KA/415V,250A 3P MCS
140UEJ7S4D25 70KA/415V, 250A 4P MCS
140UEJ7X3 70KA/415V,3P FRAME
140UEJ7X4 70KA/415V, 4P FRAME
140UEJTF3C80 80A 3P AA T/M TRIP
140UEJTF3D10 100A 3P AA T/M TRIP
140UEJTF3D12 125A 3P AA T/M TRIP
140UEJTF3D16 160A 3P AA T/M TRIP
140UEJTF3D20 200A 3P AA T/M TRIP
140UEJTF3D25 250A 3P AA T/M TRIP
140UEJTF4C80 80A 4P AA T/M TRIP
140UEJTF4D10 100A 4P AA T/M TRIP
140UEJTF4D12 125A 4P AA T/M TRIP
140UEJTF4D16 160A 4P AA T/M TRIP
140UEJTF4D20 200A 4P AA T/M TRIP
140UEJTF4D25 250A 4P AA T/M TRIP
140UEJTG3C50 20-50A 3P LSG ELEC TRIP U
140UEJTG3D10 40-100A 3P LSG ELE TRIP U
140UEJTG3D16 63-160A 3P LSG ELE TRIP U
140UEJTG3D25 100-250A 3P LSG ELE TRIP
140UEJTG4C50 20-50A 4P LSG ELEC N
140UEJTG4D10 40-100A 4P LSG ELEC N
140UEJTG4D16 63-160A 4P LSG ELEC N
140UEJTG4D25 100-250A 4P LSG ELEC N
140UEJTH3C50 20-50A 3P LSI ELEC TRIP U
140UEJTH3D10 40-100A 3P LSI ELE TRIP U
140UEJTH3D16 63-160A 3P LSI ELE TRIP U
140UEJTH3D25 100-250A 3P LSI ELE TRIP
140UEJTH4C50 20-50A 4P LSI ELEC N
140UEJTH4D10 40-100A 4P LSI ELEC N
140UEJTH4D16 63-160A 4P LSI ELEC N
140UEJTH4D25 100-250A 4P LSI ELEC N
140UEJTI3C50 20-50A 3P LSIG ELE TRIP U
140UEJTI3D10 40-100A 3P LSIG ELE TRIP
140UEJTI3D16 63-160A 3P LSIG ELE TRIP
140UEJTI3D25 100-250A 3P LSIG ELE TRIP
140UEJTI4C50 20-50A 4P LSIG ELEC N
140UEJTI4D10 40-100A 4P LSIG ELEC N
140UEJTI4D16 63-160A 4P LSIG ELEC N
140UEJTI4D25 100-250A 4P LSIG ELEC N
140UEJTL3C50 20-50A 3P LS ELEC TRIP UN
140UEJTL3D10 40-100A 3P LS ELEC TRIP U
140UEJTL3D16 63-160A 3P LS ELE TRIP UN
140UEJTL3D25 100-250A 3P LS ELE TRIP U
140UEJTL4C50 20-50A 4P LS ELEC N
140UEJTL4D10 40-100A 4P LS ELEC N
140UEJTL4D16 63-160A 4P LS ELEC N
140UEJTL4D25 100-250A 4P LS ELEC N
140UEL3F3D32 MOLDED CASE CIRCUIT BREAK
140UEL3F3D63 35KA/480V,15A 2P FF MCCB
140UEL3F4D32 MOLDED CASE CIRCUIT BREAK
140UEL3X3 35KA/415V,3P FC MCCB
140UEL3X4 35KA/415V 4P FRAME ONLY
140UEL5X3 50KA/415V,3P FC MCCB
140UEL5X4 50KA/415V 4P FRAME ONLY
140UEL7I3D63 MOLDED CASE CIRCUIT BREAK
140UEL7S3D63 70KA/415V,630A 3P MCS
140UEL7S4D63 70KA/415V,630A 4P MCS
140UEL7X3 70KA/415V,3P FC MCCB
140UEL7X4 70KA/415V 4P FRAME ONLY
140UELTF3D25 250A 3P AA T/M TRIP UNIT
140UELTF3D32 320A 3P AA T/M TRIP UNIT
140UELTF3D40 400A 3P AA T/M TRIP UNIT
140UELTF3D50 500A 3P AA T/M TRIP UNIT
140UELTF3D63 630A 3P AA T/M TRIP UNIT
140UELTF4D25 250A 4P AA T/M N=****
140UELTF4D32 320A 4P AA T/M N=****
140UELTF4D40 400A 4P AA T/M N=****
140UELTF4D50 500A 4P AA T/M N=****
140UELTF4D63 630A 4P AA T/M N=****
140UELTG3D63 250-630A 3P LSG TRIP
140UELTG4D63 250-630A 4P LSG ELEC TRIP
140UELTH3D63 250-630A 3P LSI TRIP
140UELTH4D63 250-630A 4P LSI ELEC TRIP
140UELTI3D63 250-630A 3P LSIG TRIP
140UELTI4D63 250-630A 4P LSIG TRIP
140UELTL3D63 250-630A 3P LS ELEC TRIP
140UELTL4D63 250-630A 4P LS ELEC TRIP
140UEM5F3D60 35KA/480V,15A 2P FF MCCB
140UEM5X3 50KA/400V, 3P FRAME
140UEM7X3 70KA/400V, 3P FRAME
140UEMTD3D30 300A 3P "AA" T/M TRIP UNT
140UEMTD3D35 350A 3P "AA" T/M TRIP UNT
140UEMTD3D40 400A 3P "AA" T/M TRIP UNT
140UEMTD3D45 450A 3P "AA" T/M TRIP UNT
140UEMTD3D50 500A 3P "AA" T/M TRIP UNT
140UEMTD3D60 600A 3P "AA" T/M TRIP UNT
140UEMTD3D70 700A 3P "AA" T/M TRIP UNT
140UEMTD3D80 800A 3P "AA" T/M TRIP UNT
140UEMTG3D80 800A 3P ELEC LSG TRIP UNT
140UEMTH3D80 800A 3P ELEC LSI TRIP UNT
140UEMTI3D80 8003PELEC LSIG TRIP UNIT
140UEMTL3D80 800A 3P ELEC LS TRIP UNIT
140UEN0G3E12 100KA,1250A ELEC BKR,LSG,
140UEN0G4E12 100KA,1250A ELEC BKR,LSG,
140UEN0H3E12 100KA,1250A ELEC BKR,LSI,
140UEN0H4E12 100KA,1250A ELEC BKR,LSI,
140UEN0I3E12 POWER COMPONENTS
140UEN0I4E12 100KA,1250A ELEC BKR,LSIG
140UEN0L3E12 100KA,1250A ELEC BKR,LS,3
140UEN0L4E12 100KA,1250A ELEC BKR,LS,4
140UEN5G3E12 50KA,1250A ELEC BKR,LSG,3
140UEN5G4E12 50KA,1250A ELEC BKR,LSG,4
140UEN5H3E12 50KA,1250A ELEC BRKR,LSI,
140UEN5H4E12 50KA,1250A ELEC BKR,LSI,4
140UEN5I3E12 50KA,1250A ELEC BKR,LSIG,
140UEN5I4E12 50KA,1250A ELEC BKR,LSIG,
140UEN5L3E12 50KA,1250A ELEC BKR,LS,3P
140UEN5L4E12 50KA,1250A ELEC BKR,LS,4P
140UEN7G3E12 70KA,1250A ELEC BKR,LSG,3
140UEN7H3E12 70KA,1250A ELEC BKR,SKI,3
140UEN7I3E12 70KA,1250A ELEC BKR,LSIG,
140UEN7L3E12 70KA,1250A ELEC BKR,LS,3P
140UEN7S3E12 70KA,1250A 3P MCS
140UEN7S4E12 70KA,1250A 4P MCS
140UG1C2C15 G FRAME MCCB, 2 POLE
140UG1C2C15A 14KA/480V 15A 2P FF MCCB
140UG1C2C20 G FRAME MCCB, 2 POLE
140UG1C2C20A 14KA/480V 20A 2P FF MCCB
140UG1C2C25 G FRAME MCCB, 2 POLE
140UG1C2C25A 14KA/480V 25A 2P FF MCCB
140UG1C2C30 G FRAME MCCB, 2 POLE
140UG1C2C30A 14KA/480V 30A 2P FF MCCB
140UG1C2C35 G FRAME MCCB, 2 POLE
140UG1C2C35A 14KA/480V 35A 2P FF MCCB
140UG1C2C40 G FRAME MCCB, 2 POLE
140UG1C2C40A 14KA/480V 40A 2P FF MCCB
140UG1C2C45 G FRAME MCCB, 2 POLE
140UG1C2C45A 14KA/480V 45A 2P FF MCCB
140UG1C2C50 G FRAME MCCB, 2 POLE
140UG1C2C50A 14KA/480V 50A 2P FF MCCB
140UG2C3C15 G FRAME MCCB, 3 POLE
140UG2C3C15A 22KA/480V 15A 3P FF MCCB
140UG2C3C15PD MCCB, 25kA/480V, 100A Frame, 15A FF T/M Trip
140UG2C3C15QD MCCB, 25kA/480V, 100A Frame, 15A FF T/M Trip
140UG2C3C20 G FRAME MCCB, 3 POLE
140UG2C3C20A 22KA/480V 20A 3P FF MCCB
140UG2C3C20PD MCCB, 25kA/480V, 100A Frame, 20A FF T/M Trip
140UG2C3C20QD MCCB, 25kA/480V, 100A Frame, 20A FF T/M Trip
140UG2C3C25 G FRAME MCCB, 3 POLE
140UG2C3C25A 22KA/480V 25A 3P FF MCCB
140UG2C3C25PD MCCB, 25kA/480V, 100A Frame, 25A FF T/M Trip
140UG2C3C25QD MCCB, 25kA/480V, 100A Frame, 25A FF T/M Trip
140UG2C3C30 G FRAME MCCB, 3 POLE
140UG2C3C30A 22KA/480V 30A 3P FF MCCB
140UG2C3C30PD MCCB, 25kA/480V, 100A Frame, 30A FF T/M Trip
140UG2C3C30QD MCCB, 25kA/480V, 100A Frame, 30A FF T/M Trip
140UG2C3C35 G FRAME MCCB, 3 POLE
140UG2C3C35A 22KA/480V 35A 3P FF MCCB
140UG2C3C35PD MCCB, 25kA/480V, 100A Frame, 35A FF T/M Trip
140UG2C3C35QD MCCB, 25kA/480V, 100A Frame, 35A FF T/M Trip
140UG2C3C40 G FRAME MCCB, 3 POLE
140UG2C3C40A 22KA/480V 40A 3P FF MCCB
140UG2C3C40PD MCCB, 25kA/480V, 100A Frame, 40A FF T/M Trip
140UG2C3C40QD MCCB, 25kA/480V, 100A Frame, 40A FF T/M Trip
140UG2C3C45 G FRAME MCCB, 3 POLE
140UG2C3C45A 22KA/480V 45A 3P FF MCCB
140UG2C3C45PD MCCB, 25kA/480V, 100A Frame, 45A FF T/M Trip
140UG2C3C45QD MCCB, 25kA/480V, 100A Frame, 45A FF T/M Trip
140UG2C3C50 G FRAME MCCB, 3 POLE
140UG2C3C50A 22KA/480V 50A 3P FF MCCB
140UG2C3C50PD MCCB, 25kA/480V, 100A Frame, 50A FF T/M Trip
140UG2C3C50QD MCCB, 25kA/480V, 100A Frame, 50A FF T/M Trip
140UG2C3C60 G FRAME MCCB, 3 POLE
140UG2C3C60A 22KA/480V 60A 3P FF MCCB
140UG2C3C60PD MCCB, 25kA/480V, 100A Frame, 60A FF T/M Trip
140UG2C3C60QD MCCB, 25kA/480V, 100A Frame, 60A FF T/M Trip
140UG2C3C70 G FRAME MCCB, 3 POLE
140UG2C3C70A 22KA/480V 70A 3P FF MCCB
140UG2C3C70PD MCCB, 25kA/480V, 100A Frame, 70A FF T/M Trip
140UG2C3C70QD MCCB, 25kA/480V, 100A Frame, 70A FF T/M Trip
140UG2C3C80 G FRAME MCCB, 3 POLE
140UG2C3C80A 22KA/480V 80A 3P FF MCCB
140UG2C3C80PD MCCB, 25kA/480V, 100A Frame, 80A FF T/M Trip
140UG2C3C80QD MCCB, 25kA/480V, 100A Frame, 80A FF T/M Trip
140UG2C3C90 G FRAME MCCB, 3 POLE
140UG2C3C90A 22KA/480V 90A 3P FF MCCB
140UG2C3C90PD MCCB, 25kA/480V, 100A Frame, 90A FF T/M Trip
140UG2C3C90QD MCCB, 25kA/480V, 100A Frame, 90A FF T/M Trip
