National Instruments NI-DNET - Manual (Page 66)

Appendix B Cabling Requirements
NI-DNET User Manual B-6 ni.com
Cable Specifications
Cables should meet the requirements of the DeviceNet cable specification.
DeviceNet cabling requirements can be found in the DeviceNet
Specification.
Belden cable (3084A) meets all of those requirements and should be
suitable for most applications.
Cable Lengths
The allowable cable length is affected by the characteristics of the cabling
and the desired bit transmission rates. Detailed cable length requirements
can be found in the DeviceNet Specification.
Table B-2 lists the DeviceNet cable length specifications.
Maximum Number of Devices
The maximum number of devices that you can connect to a DeviceNet port
depends on the electrical characteristics of the devices on the network. If all
of the devices on the network meet the DeviceNet specifications,
64 devices may be connected to the network.
Table B-2. DeviceNet Cable Length Specifications
Baud Rate Trunk Length
Drop Length
Maximum
Drop Length
Cumulative
500 kb/s 100 m (328 ft) 6 m (20 ft) 39 m (128 ft)
250 kb/s 250 m (820 ft) 6 m (20 ft) 78 m (256 ft)
125 kb/s 500 m (1640 ft) 6 m (20 ft) 156 m (512 ft)