Rockwell Automation 1785-LTx,D17856.2.1 Classic PLC-5 Programmable Controllers Users Manual - Manual (Page 39)

Placing System Hardware
Chapter 3
3-4
You provide the enclosure for your processor system. This enclosure
protects your processor system from atmospheric contaminants such as oil,
moisture, dust, corrosive vapors, or other harmful airborne substances. To
help guard against EMI/RFI, we recommend a steel enclosure.
Mount the enclosure in a position where you can fully open the doors. You
need easy access to processor wiring and related components so that
troubleshooting is convenient.
When you choose the enclosure size, allow extra space for transformers,
fusing, disconnect switch, master control relay, and terminal strips.
ATTENTION: Under some conditions, electrostatic
discharge can degrade performance or damage the processor
module. Read and observe the following precautions to guard
against electrostatic damage.
Wear an approved wrist strap grounding device when
handling the processor module.
Touch a grounded object to discharge yourself before
handling the processor module.
Do not touch the backplane connector or connector pins.
When not handling the processor module, keep it in its
protective packaging.
The raceway layout of a system reflects where the different types of I/O
modules are placed in I/O chassis. Therefore, you should determine
I/O-module placement prior to any layout and routing of wires. When
planning your I/O-module placement, however, segregate the modules
based on the conductor categories published for each I/O module so that
you can follow these guidelines. These guidelines coincide with the
guidelines for “the installation of electrical equipment to minimize
electrical noise inputs to controllers from external sources” in IEEE
standard 518-1982.
Protecting Your Processor
Avoiding Electrostatic
Damage
Laying Out Your
Cable Raceway