9  Dimensioning
9.1  Dimensioning instructions
The dimensioning of the COMBIVERT F5 AIC occurs to the maximum permissible rated 
inputcurrent.Thepowerspecicationsreferto400Vratedinputvoltage.
The DC current is dependent on the adjusted DC voltage and is not measured sepa-
rately.
Precharging 
Depending on the mains input circuit of the AIC unit either the „max. external charging 
current“ I
ext“ or the „max. permissible DC link capacity Cext“ must be observed  
(=> „Technical data of COMBIVERT drive converters“)!
Furthermore observe the required waiting time between two switch-on procedures to 
protect the precharging resistors. 
Mains input circuit type A:
No current limitation for external connected DC devices is available at DC terminals 
(marking ++, --) of type A. Current limitation must be ensured by the external connected 
devices. The maximum external charging current may not be exceeded (=> „Unit Data“).
Mains input circuit type D1:
The current limitation of type D for the connected devices at the DC terminals (marking 
+PA,-)occursbytheintegratedchargingcurrentlimit.Thespeciedmaximumpermis-
sible DC link capacity may not be exceeded by the connected devices (=> „Unit Data“). 
Max. permissible total charging current (I
pre) 
The current indicates the maximum expected current during the precharging procedure 
and can be used for dimensioning of the pre-charging contactor.
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 DIMENSIONING