Rockwell Automation Publication 1794-IN092F-EN-P - November 2021
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FLEX I/O Terminal Base Units Installation Instructions
Environment and Enclosure
ATTENTION:
This equipment is intended for use in a Pollution Degree 2 industrial environment, in overvoltage Category II applications (as defined in
EN/IEC 60664-1), at altitudes up to 2000 m (6562 ft) without derating.
This equipment is not intended for use in residential environments and may not provide adequate protection to radio communication services in such
environments.
This equipment is supplied as open-type equipment for indoor use. It must be mounted within an enclosure that is suitably designed for those specific
environmental conditions that will be present and appropriately designed to prevent personal injury resulting from accessibility to live parts. The enclosure
must have suitable flame-retardant properties to prevent or minimize the spread of flame, complying with a flame spread rating of 5VA or be approved for
the application if nonmetallic. The interior of the enclosure must be accessible only by the use of a tool. Subsequent sections of this publication may contain
more information regarding specific enclosure type ratings that are required to comply with certain product safety certifications.
In addition to this publication, see the following:
• Industrial Automation Wiring and Grounding Guidelines, Rockwell Automation® publication
, for more installation requirements.
• NEMA Standards 250 and IEC 60529, as applicable, for explanations of the degrees of protection provided by different types of enclosure.
WARNING:
When you insert or remove the module while backplane power is on, an electrical arc can occur. This could cause an explosion in hazardous location
installations. Be sure that power is removed or the area is nonhazardous before proceeding.
WARNING:
If you connect or disconnect wiring while the field-side power is on, an electrical arc can occur. This could cause an explosion in hazardous location
installations. Be sure that power is removed or the area is nonhazardous before proceeding.
ATTENTION:
This product is grounded through the DIN rail to chassis ground. Use zinc plated chromate-passivated steel DIN rail to assure proper grounding.
The use of other DIN rail materials (for example, aluminum or plastic) that can corrode, oxidize, or are poor conductors, can result in improper or intermittent
grounding. Secure DIN rail to mounting surface approximately every 200 mm (7.8 in.) and use end-anchors appropriately. Be sure to ground the DIN rail
properly. See the Industrial Automation Wiring and Grounding Guidelines, Rockwell Automation publication
, for more information.
Prevent Electrostatic Discharge
ATTENTION:
This equipment is sensitive to electrostatic discharge, which can cause internal damage and affect normal operation. Follow these guidelines
when you handle this equipment:
• Touch a grounded object to discharge potential static.
• Wear an approved grounding wriststrap.
• Do not touch connectors or pins on component boards.
• Do not touch circuit components inside the equipment.
• Use a static-safe workstation, if available.
• Store the equipment in appropriate static-safe packaging when not in use.
ATTENTION:
Do not remove or replace a Terminal Base unit while power is applied. Interruption of the backplane can result in unintentional operation or
machine motion.
ATTENTION:
Do not wire more than 1 conductor on any single terminal.
ATTENTION:
Personnel responsible for the application of safety-related Programmable Electronic Systems (PES) shall be aware of the safety requirements in
the application of the system and shall be trained in using the system.
WARNING:
Terminal bases 1794-TB2, 1794-TB2K, 1794-TBN, 1794-TBNK, 1794-TB3, 1794-TB3K, 1794-TB3S, 1794-TB3SK, 1794-TB3T, 1794-TB3TK, 1794-TB3TS,
1794-TB3TSK are not approved for use above 60V AC or 75V DC in ATEX/IECEx applications.
