Restriction Of Cable Lengths; Figure 6-16 Maximum Network Length; Table 6-3 Cable Length And Line Type - Hitachi S10mini LQS070 Hardware Manual

6.1.4

Restriction of cable lengths

The lengths of cables in DeviceNet are restricted. Satisfy the following restrictions when
cunstrucing a DeviceNet.
(1) Maximum network length
The maximum network length means a distance between two nodes or terminating
resistors which are located furthest from each other. It is dependent of the type of the
main line cable and the transfer rate of the network, See the figure below.
Terminating
Distance L1 between two
resistor
terminating resistors
Node
Transfer rate
500kbps
250kbps
125kbps
"L THICK" represents the length of a thick cable and "L THIN" represents the length of
a thin cable.
Greatest distance
between nodes L2
Node
Node
Maximum network length

Figure 6-16 Maximum Network Length

Table 6-3 Cable Length and Line Type

Thick cable only
100 m or shorter
100 m or shorter
250 m or shorter
500 m or shorter
24
VDC
Node
L1 (when L1 > L2)
L2 (when L1 < L2)
Main line cable
Thin cable only
L THICK + L THIN≦100 m
L THICK + 2.5 × L THIN≦250 m
L THICK + 5 × L THIN≦500 m
− 45 −
6 CABLING
Terminating
resistor
Node
Thick and thin cables