Rockwell Automation 1794-IP4/B INSTL INSTR 24V dc FLEX I/O 4 CHANNEL User Manual
Installation instructions, Flex i/o 4 channel pulse counter module, North american hazardous location approval
 
Publication 1794-IN064D-EN-P - March 2005
Installation Instructions
FLEX I/O 4 Channel Pulse Counter Module
Cat. No. 1794-IP4 Series B
North American Hazardous Location Approval
Important User Information
Solid state equipment has operational characteristics differing from those of 
electromechanical equipment. Safety Guidelines for the Application, Installation and 
Maintenance of Solid State Controls (Publication SGI-1.1 available from your local Rockwell 
Automation sales office or online at http://www.ab.com/manuals/gi) describes some 
important differences between solid state equipment and hard-wired electromechanical 
devices. Because of this difference, and also because of the wide variety of uses for solid state 
equipment, all persons responsible for applying this equipment must satisfy themselves that 
each intended application of this equipment is acceptable.
In no event will Rockwell Automation, Inc. be responsible or liable for indirect or consequential 
damages resulting from the use or application of this equipment.
The examples and diagrams in this manual are included solely for illustrative purposes. 
Because of the many variables and requirements associated with any particular installation, 
Rockwell Automation, Inc. cannot assume responsibility or liability for actual use based on the 
examples and diagrams.
No patent liability is assumed by Rockwell Automation, Inc. with respect to use of information, 
circuits, equipment, or software described in this manual.
Reproduction of the contents of this manual, in whole or in part, without written permission of 
Rockwell Automation, Inc. is prohibited.
Throughout this manual we use notes to make you aware of safety considerations.
WARNING
Identifies information about practices or circumstances that can cause 
an explosion in a hazardous environment, which may lead to personal 
injury or death, property damage, or economic loss.
IMPORTANT
Identifies information that is critical for successful application and 
understanding of the product.
ATTENTION
Identifies information about practices or circumstances that can lead to 
personal injury or death, property damage, or economic loss. Attentions 
help you:
• identify a hazard
• avoid a hazard
• recognize the consequence
ATTENTION
Environment and Enclosure
This equipment is intended for use in a Pollution Degree 2 industrial 
environment, in overvoltage Category II applications (as defined in
IEC publication 60664-1), at altitudes up to 2000 meters without
derating.
This equipment is considered Group 1, Class A industrial equipment 
according to IEC/CISPR Publication 11. Without appropriate
precautions, there may be potential difficulties ensuring
electromagnetic compatibility in other environments due to conducted
as well as radiated disturbance.
This equipment is supplied as "open type" equipment. 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 interior of the enclosure must be accessible only by the use
of a tool. Subsequent sections of this publication may contain
additional information regarding specific enclosure type ratings that are
required to comply with certain product safety certifications.
See NEMA Standards publication 250 and IEC publication 60529, as 
applicable, for explanations of the degrees of protection provided by
different types of enclosure. Also, see the appropriate sections in this
publication, as well as the Allen-Bradley publication 1770-4.1
("Industrial Automation Wiring and Grounding Guidelines"), for
additional installation requirements pertaining to this equipment.
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. Repeated electrical
arcing causes excessive wear to contacts on both the module and its
mating connector. Worn contacts may create electrical resistance
that can affect module operation.
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
FLEX I/O is grounded through the DIN rail to chassis ground. Use
zinc plated yellow-chromate steel DIN rail to assure proper
grounding. The use of other DIN rail materials (e.g. aluminum,
plastic, etc.) that can corrode, oxidize, or are poor conductors, can
result in improper or intermittent grounding.
ATTENTION
Preventing Electrostatic Discharge
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.
• If available, use a static-safe workstation.
The following information applies when operating 
this equipment in hazardous locations:
Informations sur l’utilisation de cet équipement en 
environnements dangereux :
Products marked “CL I, DIV 2, GP A, B, C, D” are suitable 
for use in Class I Division 2 Groups A, B, C, D, Hazardous 
Locations and nonhazardous locations only. Each 
product is supplied with markings on the rating 
nameplate indicating the hazardous location 
temperature code. When combining products within a 
system, the most adverse temperature code (lowest “T” 
number) may be used to help determine the overall 
temperature code of the system. Combinations of 
equipment in your system are subject to investigation by 
the local Authority Having Jurisdiction at the time of 
installation.
Les produits marqués "CL I, DIV 2, GP A, B, C, D" ne 
conviennent qu’à une utilisation en environnements de 
Classe I Division 2 Groupes A, B, C, D dangereux et non 
dangereux. Chaque produit est livré avec des marquages 
sur sa plaque d’identification qui indiquent le code de 
température pour les environnements dangereux. Lorsque 
plusieurs produits sont combinés dans un système, le 
code de température le plus défavorable (code de 
température le plus faible) peut être utilisé pour 
déterminer le code de température global du système. Les 
combinaisons d’équipements dans le système sont 
sujettes à inspection par les autorités locales qualifiées 
au moment de l’installation.
EXPLOSION HAZARD
• Do not disconnect
equipment unless power has 
been removed or the area is 
known to be nonhazardous. 
• Do not disconnect
connections to this equipment 
unless power has been 
removed or the area is known 
to be nonhazardous. Secure 
any external connections that 
mate to this equipment by 
using screws, sliding latches, 
threaded connectors, or other 
means provided with this 
product.
• Substitution of components
may impair suitability for Class 
I,
Division 2.
• If this product contains
batteries, they must only be 
changed in an area known to 
be nonhazardous.
RISQUE D’EXPLOSION
• Couper le courant ou s’assurer
que l’environnement est classé 
non dangereux avant de 
débrancher l'équipement.
• Couper le courant ou s'assurer
que l’environnement est classé 
non dangereux avant de 
débrancher les connecteurs. Fixer 
tous les connecteurs externes 
reliés à cet équipement à l'aide 
de vis, loquets coulissants, 
connecteurs filetés ou autres 
moyens fournis avec ce produit.
• La substitution de composants
peut rendre cet équipement 
inadapté à une utilisation en 
environnement de Classe I, 
Division 2.
• S’assurer que l’environnement
est classé non dangereux avant 
de changer les piles.
WARNING
AVERTISSEMENT