Rockwell Automation 1747-L5xx SLC 500 Modular Hardware Style User Manual - Manual (Page 114)

Publication 1747-UM011G-EN-P - June 2008
114 Wiring Your I/O Modules
Preparing Your Wiring
Layout Careful wire routing within the enclosure helps to cut down electrical
noise between I/O lines. Follow these rules for routing your wires.
• Route incoming power to the controller by a separate path from
wiring to I/O devices. Where paths must cross, their intersection
should be perpendicular.
• If wiring ducts are used, allow for at least 50.8 mm (2 in.)
between I/O wiring ducts and the controller. If the terminal
strips are used for I/O wiring, allow for at least two inches
between the terminal strips and the controller.
• Limit the cable length for the TTL input module to 15.24 m
(50 ft) per point and 3.05 m (10 ft) per point for the TTL output
module. Use low power dc I/O wiring even though it is less
tolerant to electrical noise.
• Segregate I/O wiring by signal type. Bundle wiring with similar
electrical characteristics together.
Wires with different signal characteristics should be routed into the
enclosure by separate paths. Refer to Allen-Bradley Programmable
Controller Grounding and Wiring Guidelines, publication 1770-4.1.
IMPORTANT
Do not run signal or communication wiring and power
wiring in the same conduit.
ATTENTION
Handle the TTL module by its ends, not metallic
surfaces. Electrostatic discharges can damage the
module. Do not expose the TTL module to electrostatic
charges.
ATTENTION
If the controller is being installed within a potentially hazardous
environment (that is, Class I, Division 2), all wiring must comply
with the requirements stated in the National Electrical Code
501-4 (b).