Rockwell Automation Allen-Bradley 1769-IF4, Руководство пользователя

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Publication 1769-UM002B-EN-P - July 2005
2-4 Installation and Wiring
Remove Power
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 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. Refer to the module’s heat dissipation specification.
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.
System Assembly
The module can be attached to the controller or an adjacent I/O module before
or after mounting. For mounting instructions, see Panel Mounting Using the
Dimensional Template on page 2-7, or DIN Rail Mounting on page 2-8. To
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.