power distribution - Siemens

14BUSWAYSYSTEMSBusway SystemsReducers and Phase Rotation FittingsFused Reducers, Dimensions (standard/min.)Dimensions Inches (mm)Ampere Rating“A”AL L-Rated225 — 11.4 (289)400 — 11.4 (289)600 — 11.4 (289)800 400 11.4 (289)1000 600 11.4 (289)1200 800 12.5 (318)1350 1000 13.5 (343)1600 1200 14.6 (372)2000 1350,1600 16.9 (429)2500 2000 19.6 (498)3000 2500 21.3 (541)3200 2000 22.9 (582)4000 3000,3200 31.5 (800)CU M-Rated225 — 10.4 (264)400 — 10.4 (264)600 — 10.4 (264)800 400 10.4 (264)1000 — 10.4 (264)1200 600 11.0 (280)1350 800 11.6 (296)1600 1000 12.6 (321)2000 1200,1350 14.1 (359)— 1600 14.6 (372)2500 2000 16.6 (423)3000 — 17.9 (455)3200 — 18.9 (480)4000 2500,3000,3200 20.9 (531)5000 4000 31.5 (800)SelectionFused ReducersThe National Electric Code requires over current protection whenbusway systems are reduced in ampacity. A fused reducer is used toreduce the allowable ampere rating in those sections of the buswaythat do not require a higher rating (i.e. at branch circuit junctures).Fused ReducerSuffix RFRFNon-Fused ReducersNon-fused reducers are used in conjunction with the followingexception to the Fused Reducer in the National Electric Code: “Forindustrial establishments only,omission of over current protectionshall be permitted at points where busways are reduced in ampacity,provided that the length of the busway having the smaller ampacitydoes not exceed 50 ft. and has an ampacity of at least equal to onethirdthe rating or setting of the over current device next back on theline, and provided that such busway is free from contact withcombustible material.” Special joint stack connections are providedfor non-fused reducer connections. Consult factory for specific designguidelines.Phase Rotation Fittings, Dimensions (standard/min.)Dimensions Inches (mm)Ampere Rating“A”AL L-Rated225 — 7.9 (200)400 — 7.9 (200)600 — 7.9 (200)800 400 8.5 (216)1000 600 9.4 (239)1200 800 10.5 (267)1350 1000 11.5 (293)1600 1200 12.6 (321)2000 1350,1600 14.9 (376)2500 2000 17.6 (447)3000 2500 19.8 (503)3200 2000 21.3 (541)4000 3000,3200 24.3 (617)CU M-Rated225 — 7.9 (200)400 — 7.9 (200)600 — 7.9 (200)800 400 7.9 (200)1000 — 8.4 (213)1200 600 9.0 (229)1350 800 9.6 (245)1600 1000 10.6 (270)2000 1200,1350 12.1 (372)— 1600 12.6 (321)2500 2000 14.6 (200)3000 — 15.8 (402)3200 — 17.3 (439)4000 2500,3000,3200 19.3 (490)5000 4000 23.3 (592)Phase-Rotation FittingsPhase-rotation fittings can be used when the application requires aphase rotation in the power supply. Phase rotation fittings can beordered for “phase and ground”, “phase only” and “ground only”rotations.Phase Rotation FittingSuffix TRPG, Phase and GroundTRPO, Phase OnlyTRGO, Ground OnlyPhase Rotation Examples14-36Siemens Power Distribution & Control, SPEEDFAX 2007-2008 Product Catalog