Omron 3G8F7-CRM21, User Manual

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166
Wiring Formations
Section E-2
E-2-2 Unrestricted Wiring Formation
In this formation, there is no distinction between the trunk line and branch
lines. There are no wiring restrictions as long as the total cable length per
segment does not exceed 200 m.
There is also no limit in the number of branches.
The formation to be used is determined automatically by the type of cable
used and the required data rate.
* Trunk lines cannot have T-branch connections when the data rate is 4 Mbps.
Only multidrop connections can be used.
The following table shows the conditions and restrictions for each formation.
Slave Unit
Terminating Resistor
Repeater Unit
Slave Unit
Slave Unit
Slave Unit
Slave Unit
Terminating
Resistor
Master Board
Cable type Data rate
4 Mbps 3 Mbps 1.5 Mbps 93.75 kbps
Round cable I Trunk-Branch * Trunk-Branch Trunk-Branch Trunk-Branch
Round cable II
Flat Cable I
and II
Trunk-Branch * Trunk-Branch Trunk-Branch Unrestricted
Item Wiring formation
Trunk line-branch line
formation
Unrestricted wiring
formation
Master Board
location End of network Anywhere in network (not
necessarily at the end)
Maximum number of
Slave Units
connectable to a
single branched line 1 or 3 depending on the cable
type and data rate No restrictions
Terminating Resistor
location On the opposite end of the
trunk line or a sub-trunk line
from the Master Board or a
Repeater Unit respectively On the most remote end from
the Master Board or a
Repeater Unit