Rockwell Automation 1770 DH,DHII,DH485 CABLE - Manual (Page 31)

Planning a Data Highway or Data Highway Plus
Cable System
Chapter 2
2-15
Group conductor cables fitting this description: Examples: Into this
category:
IntraĆenclosure - Interconnect the system components
within an enclosure
• corresponds to NEC articleĆ725 classes 2 & 3
• corresponds to IEEE levels 1 (high susceptibility) &
2 (medium susceptibility)
Category 3 • lowĆvoltage dc power cables - provide backplane
power to the system components
• communication cables - to connect between system
components within the same enclosure
NOTE: Remote I/O, DH, and DH+ networks must be made of catalog number 1770ĆCD cable or a cable from the approved vendor list.
DHĆ485 networks must be made of a cable from the approved vendor list.
Route Conductors
To guard against coupling noise from one conductor to another, follow the
general guidelines shown in Table 2.C when routing wires and cables (both
inside and outside of an enclosure). Where it is stated that cables must be
in separate raceways, they can be routed in the same ladder or trough if
barriers are used as required and defined by NEC to provide the separation
specified in Table 2.C. Use the spacing given in these general guidelines
with the following exceptions:
where connection points (for conductors of different categories) on end
devices are closer together than the specified spacing
application-specific configurations for which the spacing is described in
a publication for that specific application