Rockwell Automation 1790D-NOV2/TNOV2 CompactBlock LDX Analog Modules - Manual (Page 72)

Publication 1790-UM001A-EN-P - March 2002
B-4 PROFIBUS Modules Installation, Wiring, Module Data, Status and Channel Configuration
Remove Power
General Considerations Reducing Noise
Most applications require installation in an industrial enclosure to
reduce the effects of electrical interference. Analog inputs and outputs
are highly susceptible to electrical noise. Electrical noise coupled to
the analog inputs will reduce the performance (accuracy) of the
module.
Group your modules in the enclosure 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.
In addition, route shielded, twisted-pair analog input and output
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 or expansion 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.