Rockwell Automation 57C329 Remote I/O Communications, AutoMax - Manual (Page 35)

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3.3.3 Chemical and Thermal Isolation
The Remote I/O coaxial cable system must be protected from
damage caused by the following factors:
D Oil, grease, acids, caustics, and other harsh and/or hazardous
chemicals that might damage the cable's outer jacket, adapters,
connectors, and terminating loads.
D Water, steam, and other liquids that could corrode connectors,
adapters, and terminating loads.
D Open flame, steam lines, and any equipment with a temperature
higher than the cable operating temperature.
3.3.4 Physical Isolation
Use the following guidelines to prevent physical damage to the
coaxial cable:
D Protect the cable from abrasion, vibration, moving parts, and
personnel traffic.
D Avoid intersecting a cable route with the regular routes of cranes,
forklifts, and similar equipment.
D Prevent the cable from contacting abrasive surfaces such as
concrete.
3.4 Cable System Construction
Construction of the Remote I/O coaxial cable system consists of the
following steps. Each step is described in detail in the sections that
follow:
Step 1.
Inspect and test all cable before installation.
Step 2. Pull the first cable segment.
Step 3. Terminate each end of this cable segment with a BNC
plug connector.
Step 4. Test this cable segment.
Step 5. Pull the next cable segment and repeat steps 3 and 4.
Continue until all segments have been installed.
Step 6. Assemble the complete cable system. Connect cables to
the appropriate taps and tee adapters. Connect the
terminating loads to the taps or tee adapters at both ends
of the cable system. Connect the drop cables to the taps.
3.4.1 Cable Inspection and Testing
Inspect and test the cable before the installation. This will ensure that
signal attentuation does not exceed the expected values at
frequencies of interest (as specified in Appendix F), and that internal
discontinuity that can cause reflections does not exist. Many cable
suppliers (including Belden) pretest and certify the cable before
shipment. However, the cable can be damaged when shipped or
stored improperly. Because of this, it is very important to test the
cable before installation. To test for damage, shorts, or discontinuity,
use a time domain reflectometer (TDR) or a return loss meter.