Dc Interface, Principle Of Operation; Commissioning The Dc Interface When Option K90 Is Being Used; Commissioning The Dc Interface Without Option K90 - Siemens SINAMICS S120 Manual

Options
8.25 L37, DC interface incl. pre-charging input circuit for the relevant DC link capacitance
8.25.2.2

DC interface, principle of operation

The DC interface connects/disconnects the DC busbar and the Motor Module in the Cabinet
Kit. This option is implemented with a pre-charging input circuit. A fuse switch disconnector,
which is installed as a standard feature between the Motor Module and the DC busbar, as
well as pre-charging resistors and contactor disconnectors connect the Motor Module with
the DC busbar.
The contactor disconnector is triggered via a time relay, which is activated by the switch
installed in the door.
The DC interface should only be switched and the fuse switch disconnector should only be
unplugged when not under load. A checkback signal is transferred via the internal
interconnection to the CU320-2 Control Unit which locks out switching under load.
8.25.2.3

Commissioning the DC interface when option K90 is being used

With option K90, a checkback contact from the fuse switch disconnector is factory-linked to
digital input 3 of the Control Unit.
CAUTION
If changes are made to the factory-set parameters, you must verify that the "Infeed ready"
checkback signal is connected to digital input 3 on the Control Unit (p0864 = r722.3).
If parameter p0864 is not wired to the checkback signal, it is possible to operate the switch
under load. This can shorten the service life of the switch.
8.25.2.4

Commissioning the DC interface without option K90

If the cabinet does not contain a Control Unit (option K90), terminal -X41.12 of the DC
interface must be connected by the customer to a digital input of the Control Unit assigned to
the controlled Motor Module. The 24 V DC supply for the checkback signal is provided via
terminal -X41.11 (see circuit diagram).
The digital input to which the checkback contact is assigned must be connected to the
"Infeed operation" parameter (p0864) of the drive object [Drive_1].
Example of digital input 3 on the Control Unit:
[Drive_1] p0864 = [CU] r722.3
The interconnection can be made with the STARTER commissioning tool or the AOP30
operator panel (option K08).
CAUTION
If parameter p0864 is not wired to the checkback signal, it is possible to operate the switch
under load. This can shorten the service life of the switch.
416
CAUTION
Cabinet Modules
Manual, (GH5), 05/2010, A5E03263538A