Rockwell Automation 1769-IF16V Compact High Density Analog Input Modules - Manual (Page 15)

Publication 1769-UM018A-EN-P - October 2008 15
Installation and Wiring Chapter 2
Remove Power
Reduce Noise
Most applications require installation in an industrial enclosure to
reduce the effects of electrical interference. Analog inputs are highly
susceptible to electrical noise. Electrical noise coupled to the analog
inputs will reduce the performance (accuracy) of the module.
Group your modules to minimize adverse effects from radiated
electrical noise and heat. Consider the following conditions when
selecting a location for the analog module. Position the module:
•
away from sources of electrical noise such as hard-contact
switches, relays, and ac motor drives.
•
away from modules which generate significant radiated heat,
such as the 1769-IA16 module. Refer to the module’s heat
dissipation specification.
In addition, route shielded, twisted-pair analog input wiring away
from any high-voltage I/O wiring.
Protecting the Circuit Board from Contamination
The printed circuit boards of the analog modules must be protected
from dirt, oil, moisture, and other airborne contaminants. To protect
these boards, the system must be installed in an enclosure suitable for
the environment. The interior of the enclosure should be kept clean
and the enclosure door should be kept closed whenever possible.
ATTENTION
Remove power before removing or inserting this module. When
you remove or insert a module with power applied, an electrical
arc may occur. An electrical arc can cause personal injury or
property damage by:
•
sending an erroneous signal to your system’s field devices,
causing unintended machine motion.
•
causing an explosion in a hazardous environment.
Electrical arcing causes excessive wear to contacts on both the
module and its mating connector and may lead to premature
failure.