Start-up 101Connecting voltage to inverter unitThe table below describes how to connect voltage to the inverter unit.Action InformationWARNING! When connecting voltage to the supply unit, the DC busbars will become live, as will allthe inverters connected to the DC bus.Make sure it is safe to connect voltage to the supply unit. Ensure that• nobody is working on the unit or circuits that are wired from outside circuits to the drive system• it is safe to start the motor• the cabinet doors are closed.WARNING!Inverter units with a DC switch-disconnector:Some types of inverter module may be energized through a charging circuit even when the DCswitch-disconnector is open or the DC fuses removed.Inverter cubicles with frame R1i…R5i modules:Before closing the main DC switch-disconnector of the cubicle, leave open the fuse disconnectors of thoseinverter modules that need not be powered at this time. Do not open or close any fuse disconnectors underload.FRAME R1i…R7i INVERTER UNITS EQUIPPED WITH DC SWITCH-DISCONNECTORS (OR FUSEDISCONNECTORS)Close the DC switch/disconnector (or fuse disconnectors) of theinverter units that are to be powered up.Close the common DC switch/disconnector for all modules if thecubicle is fitted with one.As soon as the DC bus is energizedlater on in this procedure, thecapacitor banks of the invertermodules are charged automatically.FRAME (n×)R8i INVERTER UNITS EQUIPPED WITH MAIN DC SWITCH-DISCONNECTORThese units are equipped with a charging circuit and can be connected to a powered DC bus. See below.POWERING THE DC BUSWARNING! Before closing the main contactor/air circuit breaker, make sure that sufficient inverterpower is connected to the intermediate (DC) bus.As a rule of thumb,• the sum power of the inverters connected must be at least 30% of the sum power of all inverters• the sum power of the inverters connected must be at least 30% of the rated power of the brake unit (Pbr.max )(if present).If the above-mentioned rules are not followed, the DC fuses of the connected inverter units may blow, or thebrake chopper (if present) may be damaged.Ensure that the number of inverters connected to the DC bus issufficient.See the WARNING above.Close the main contactor (or breaker) of the supply unit. The DC bus is now powered, alongwith all inverters that are connectedto it.FRAME (n×)R8i INVERTER UNITS EQUIPPED WITH MAIN DC SWITCH-DISCONNECTORClose the charging switch [Q10]. Wait until the green “chargingfinished” lamp lights.The DC capacitors of the modules ofthe inverter unit are charged.Close the DC switch/disconnector [Q2]. Open the charging switch[Q10].The inverter unit is now powered.
