DC link capacitance

DC link capacitance 1:

Observe the maximum chargeable DC link capacitance

The maximum chargeable DC link capacitance must be considered when designing the machine or plant:

    • The capacitances can be taken from the table below.
    • The power supply modules charge up the entire DC link when the mains supply is first switched on.

    Maximum chargeable DC link capacitance

    Module

    230 VAC

    400 VAC

    480 VAC

    AX8600-0000

    25000

    8500

    6000

    AX8620-0000

    25000

    8500

    6000

    AX8640-0000

    40000

    13500

    9500

    AX8525-0000

    70000

    23000

    13000

    AX8540-0000

    70000

    23000

    13000


    Special cases

    AX8600 DC power supply module

    If further axis and option modules are connected to an AX8600 DC power supply module that is coupled to the previous group in the DC link, the DC link capacitance of this new group does not have to be taken into account. The AX8600 module has its own charging circuit.

    AX8831/AX8832 coupling module for AMP8000

    AMP8805 distribution modules that are connected to an AX883x coupling module do not have to be taken into account in the chargeable DC link capacitance calculation, as the coupling modules have their own charging circuit.

    DC link capacitance 2:

    Maximum chargeable DC link capacitance at 400 VAC

    The system includes:

      •   1 x AX8640-0000 with   625 µF
      • 10 x AX8206-0000 with 1350 µF
      •   1 x AX8810-0000 with 1755 µF
      • That makes a total capacitance of 3730 µF.
      • The system is permissible, because a power supply module on the 400 VAC supply network can charge up a capacitance of 13500 µF.
      DC link capacitance 3:

      Charging time DC link capacitance

      Charging time of the DC link when switched on the first time:

      The charging time is calculated as follows:

      • Tau = R x C
      • After about 5 Tau the charging time is completed.

       

      Examples

      AX8620 at 400 VAC with maximum number of axis modules:

      AX8540 at 400 VAC with maximum number of axis modules: