Lenze EMF2191IB - Manual (Page 27)

Installation
Electrical installation
POWERLINK
5
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27 EDSMF2191IB EN 2.0
Topologies in the POWERLINK network segment
)
Note!
The use of class 1 hubs and switches inside the POWERLINK network segment
is not permitted.
Inside the segment only Ethernet hubs may be used as infrastructure elements. The hubs
must meet the requirements on class 2 repeaters acc. to IEEE 802.3u.
For this purpose, Lenze offers the dual hub integrated into the communication module and
the separate eight−fold hub, type E94AZCEH.
Class 1 hubs and switches are not permissible since they have considerably longer delay
times for the frame forwarding and a bigger jitter. Both sizes reduce the real−time
capability and dynamics.
The cable length between both nodes is limited to 100 m.
The topology rules (IEEE 802.3u) required for controlling the collisions may be violated in
the POWERLINK network segment since according to the POWERLINK access order, frame
collisions are prevented. This enables a structure of lines and any hybrid forms between
star and line topology.
Recommended topology
For an easy configuration and due to many possible topology variants we recommend to
create networks according to the following rules:
1. Create slave groups with up to 10 nodes
2. Connect groups in star shape to the master (managing node).
3. For more than 2 groups: Use external 8−port hubs, e. g. Lenze hub E94AZCEH.
Exception: For maximally 2 groups, these are directly connected to the two ports of the
communication module.
Hub
Master
1. slave group
2. slave group
Fig. 5−2 Star topology for 1 to 2 slave groups
4. Connect slave groups to the master via one external hub each.
– For max. 7 slave groups one hub is sufficient.
– For more than 7 slave groups, use further hubs.
– The groups can be distributed on the hubs just as you like.