YASKAWA SGD7S Product Manual page 130

4.7 DeviceNet System Configuration
4.7.3 Precautions for Connecting DeviceNet Communications Cables
The maximum network length is determined by the type of cable, as shown in the following
table.
Baud Rate (Kbps)
Information
Drop Line Lengths
The drop line length is the length of the line from the branch point from the trunk line to the far-
thest node on the drop line.
The maximum drop line length is 6 m. A drop line can be branched out into other drop lines.
Total Drop Line Length
The total drop line length is the total length of all of the drop lines.
 Length Limit
The total drop line length must be within the allowable range, and each drop line must be 6 m
or less.
The following table shows the total drop line length, which depends on the baud rate.
Baud Rate
(kbps)
500
250
125
4-42
Maximum Network Length (Unit: m)
Thick Cable
500
250
125
You can use both thick cables and thin cables to connect different nodes in the same net-
work. The maximum network length will be shorter than when only thick cables are used.
The cable lengths must meet the following restrictions.
Baud Rate (Kbps) Maximum Network Length
L
500
THICK
250 L
THICK
125 L
THICK
Note: L : Length of thick cable
THICK
L : Length of thin cable
THIN
Total Drop Line Length
39 m max.
78 m max.
156 m max.
Thin Cable
100
250
500
≤ 100 m
+ L
THIN
×
≤ 250 m
+ 2.5 L
THIN
×
≤ 500 m
+ 5.0 L
THIN
100
100
100