Omron CRT1 - 10-2009, Operation Manual

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36
Wiring Formations
Section 2-2
Unrestricted Wiring
Formation
With this wiring formation, there is no distinction between the trunk line and
branch lines. Wiring can be performed without restrictions as long as the total
cable length per segment is no longer than 200 m. There is also no limit in the
number of branches.
Relation between Baud
Rate and Communications
Cable The Cables that can be used and the required baud rates are automatically
determined by whether a trunk line-branch line formation or an unrestricted
wiring formation is used.
Note (1) If a baud rate of 4 Mbps is used, branching is not possible from the trunk
line. (Only multidrop connections are possible.)
(2) If a baud rate of 4 Mbps is used, branching and multidrop connections are
not possible from the trunk line. (There are no Multidrop Connectors for
Flat Cable II.)
The following table shows the conditions and restrictions for each formation.
Segment range
Segment range
Master Unit
Slave Unit
Terminating
Resistor
Repeater Unit
Slave Unit
Slave Unit
Slave Unit
Slave Unit
Terminating
Resistor
Cable type Baud rate
4 Mbps 3 Mbps 1.5 Mbps 93.75 kbps
Round cable I Trunk line -
branch line wir-
ing formation
(See note 1.) Trunk line -
branch line wir-
ing formation Trunk line -
branch line wir-
ing formation Trunk line -
branch line wir-
ing formation
Round cable II Unrestricted
wiring forma-
tions
Flat Cable I
Flat Cable II --- (See note
2.)
Item Wiring formation
Trunk line-branch line formation Unrestricted wiring formation
Master Unit location End of network Anywhere in network (not necessarily at the
end)
Maximum number of Slave
Units connected to any one
branch line 1 or 3 depending on the cable type and
baud rate No restrictions
Terminating Resistor location On the opposite ends of the trunk line and
all sub-trunk lines from the Master Unit and
each Repeater Unit On the most remote ends from the Master
Unit and each Repeater Unit