5
KNX PS640-IP as a backbone and
line coupler
The physical address assigned to the KNX PS640-IP determines whether the device
operates as a line or backbone coupler. If the physical address is in the form of x.y.0 (x,
y: 1..15), the router operates as a line coupler. If it is in the form of x.0.0 (x: 1..15), the
router acts as a backbone coupler.
Attention:
If the KNX PS640-IP is used as a backbone coupler (x.0.0), there must be no
KNX IP Router in the topology beneath it. For example, if a KNX PS640-IP has the
physical address of 1.0.0, there must be no KNX IP Router with the address 1.1.0.
If the KNX PS640-IP is used as a line coupler (x.y.0), there must be no KNX IP Router in
the topology above it. For example, if a KNX PS640-IP has the physical address of 1.1.0,
there must be no KNX IP Router with the address 1.0.0.
The KNX PS640-IP has a filter table and thus contributes to reducing bus load. The filter
table is automatically generated by the ETS.
Because of the speed difference between the Ethernet (10 Mbit/s) and KNX (9.6 kbit/s), a
far greater number of telegrams can be transmitted on IP. If several consecutive
telegrams are transmitted on the same line, they must be buffered in the router to avoid
telegram loss. The KNX PS640-IP 750 has a memory for 150 telegrams (from IP to
KNX/EIB).
Bus access (KNXnet/IP Tunnelling)
The Power Supply System KNX PS640-IP can be used as an interface to KNX. KNX can
be accessed from any point in the LAN. For this purpose, a second physical address
must be assigned in the ETS. Please refer to chapter “ETS Connection Manager”.
