power distribution - Siemens

Motor Control CentersProduct OverviewFor ease in wiring and inspection,terminal blocks are mounted on aswing-out side barrier.The horizontal bus compartment isisolated from the horizontal wirewaysby a crystal clear polycarbonatebarrier that makes visible andinfrared maintenance inspectiona breeze. The barrier is easilyremoved when access to thehorizontal bus is required.A racking lever on all plug-in unitsensures that they are fully engagedwith the vertical bus. An interlockwith the disconnect device ensuresthat a plug-in unit is not inserted orremoved from the vertical bus whenthe unit is energized.Horizontal bus design keeps the busin the top 12" of the structure, neverbehind units, for easy maintenanceand accessibility.A positive stop in the “TEST”position indicates that a plug-inunit is fully withdrawn from thevertical bus.Copper bus and heavy-duty insulators safely distributepower to sections. Copper bus, standard throughout, isconservatively rated at 50-degree rise and provides up toan optional 100,000A withstand capacity.Pilot devices are mounted on a sturdyformed-metal panel attached withtwo captive screws to the MCC unitdoor for easy access to internalcomponents. For unit removal andtest, the pilot device panel is easilyremoved from the door and mountdon the unit.A copper clip on plug-in unitsengages and grounds units atall times.The unit disconnect operating handlefeatures a simple, rugged design.“ON” and “OFF” are clearly indicatedby position, color and word. The“TRIP” indication is clearly displayedon circuit breaker equipped units.15MOTOR CONTROLCENTERSA positive stop mechanism preventsthe unit from falling out of thestructure during unit removal.Important Additional Features: All wiring and components meet or exceed therequirements of UL, CSA, ENEMA, EEMAC, andNEC Pre-wired components are professionally harnessedto industrial terminal blocks Full depth wire tie rods are standard in each verticalwireway White interior increases visibility for easy wiring,maintenance and inspection Modular units are fully interchangeable Each TIASTAR MCC is designed to satisfy your mostexacting specifications White on black base operating handle is easy toidentifyA screwdriver operated defeatermechanism allows access toan energized unit byauthorized personnel.All doors swing open a minimumof 110° for easy unit accessand removal.Plug-in unit stab assemblies includeself-aligning stab clips with springsteel backup springs. Wires from thestab clips to the line-side of the circuitbreaker or disconnect switch arecontained in the stab housing and areisolated phase-to-phase until thewires enter the MCC.Siemens Power Distribution & Control, SPEEDFAX 2007-2008 Product Catalog 15-5