NORD Drivesystems BU0270 - Manual (Page 21)

2 Assembly and installation
BU 0270 GB Subject to technical amendments 21
2.2.3 Configuration and addressing
The configuration of the bus module via the hardware is restricted to the possibilities for
• termination of the system bus, if the bus module forms the physical termination at the system bus level,
and the
• addressing at the field bus level ("Second Address"), if automatic addressing via the NMT master is not
desired.
For this, 11 DIP switches are available in a 12 pin DIP switch block on the inside of the bus module. The
address which is set can be read out via the SK TU4-ECT parameter (P181).
Second Address (Bus address via DIP switches)
Normally, the EtherCAT master assigns the addresses to the bus participants according to their physical
sequence on the bus. In modular applications, in which entire groups of bus participants are disconnected, the
control unit must continuously adapt its bus configuration.
This reconfiguration can be avoided by means of the so-called "Hot Connection Group" functionality and the
DIP address of the SK TU4-ECT. With this functionality, the bus module is only accessed via the DIP address.
The position of the module in the EtherCAT line is irrelevant. Configured bus modules can still be removed or
added at any time without the necessity for an adaptation in the System Manager. Therefore various
configurations of the EtherCAT bus can be operated with a single SPS project. Assignment to the SPS
variables is unique and always remains in effect.
The "Second Address" is derived from the SK TU4-ECT DIP switches. This is read in once when the bus
module is powered on.
The setting in the TwinCAT System Manager is described in Section 4.3.
ATTENTION
Devices without "Second Address" functionality must always be physically located at the
start of the bus. A device without this functionality may not follow a device with "Second
Address" functionality in the EtherCAT bus line.