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Installation Instructions
FLEX I/O 4 Channel Pulse Counter Module
Cat. No. 1794-IP4 Series B
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
IMPORTANT
ATTENTION
ATTENTION
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.
Identifies information that is critical for successful application and
understanding of the product.
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
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 infor mation 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
WARNING
ATTENTION
ATTENTION
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.
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.
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 inter mittent grounding.
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.
North American Hazardous Location Approval
The following information applies when operating
this equipment in hazardous locations:
Products marked “CL I, DIV 2, GP A, B, C, D” are suita ble
for use in Clas s 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 mos t adverse temperatur e 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 Autho rity Having Jurisdictio n at the time of
installation.
WARNING
EXPLOSION HAZARD
• Do not disc onnect
equipment unles s power has
been removed or the area is
known to be no nhazardous.
• Do not disc onnect
connections to this equipment
unless power has been
removed or the area is know n
to be nonhazardous. Secure
any external co nnections that
mate to this equipment by
using screws, slidin g latches,
threaded conn ectors, or other
means provided with this
product.
• Substitu tion of components
may impair suitability for Class
I,
Division 2.
• If this product contains
batteries, they m ust only be
changed in an area known to
be nonhazardous.
Informations sur l’utilisation de cet équipement en
environnements dangereux :
Les produits marqués "CL I, DIV 2, GP A, B, C, D" ne
conviennent qu’à un e utilisation en environnements de
Classe I Divisio n 2 Groupes A, B, C, D dangereux et non
dangereux. Ch aque produit est livré avec des marquages
sur sa plaque d’id entification qui indiquent le code de
température pour les environnements dangereux. Lorsque
plusieurs prod uits sont combinés dans u n système, le
code de tempé rature le plus défavorab le (code de
température le plus faible) peut être utilisé pour
déterminer le code de température global du système. Les
combinaisons d’ équipements dans le s ystème sont
sujettes à inspection par les autorités locales qua lifiées
au moment de l’ installation.
AVERTISSEMENT
RISQUE D’EXPLOSION
• Couper le courant ou s’assurer
que l’environnement est classé
non dangereu x avant de
débrancher l'équipement.
• Couper le courant ou s'assurer
que l’environnement est classé
non dangereu x avant de
débrancher les connecteurs. Fixer
tous les connecteurs externes
reliés à cet éq uipement à l'aide
de vis, loquets coulissants,
connecteurs filetés ou autres
moyens fourni s avec ce produit.
• La substitut ion de composants
peut rendre cet équipement
inadapté à un e utilisation en
environnement de Classe I,
Division 2.
• S’assurer que l’environnement
est classé non dangereux avant
de changer les piles.
Publication 1794-IN064D-EN-P - March 2005
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2
Even Numbered I/O Terminals 0 thru 14
Installing Your Pulse Counter Module
7
3
1
2
6
4
The module mounts on a 1794 terminal base.
ATTENTION
1. Rotate the keyswitch (1) on the terminal base (2) clockwise to position
1 as required for this type of module.
2. Make certain the flexbus connector (3) is pushed all the way to the left
to connect with the neighboring termbase/adapter. You cannot install
the module unless the connector is fully extended.
3. Make sure the pins on the bottom of the module are straight so they
will align properly with the connector in the terminal base.
WARNING
4. Position the module (4) with its alignment bar (5) aligned with the
groove (6) on the terminal base.
5. Press firmly and evenly to seat the module in the terminal base unit.
The module is seated when the latching mechanism (7) is locked into
the module.
During mounting of all devices, be sure that all debris
(metal chips, wire strands, etc.) is kept from falling into
the module. Debris that falls into the module could
cause damage on power up.
If you remove or insert the module while the 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.
5
Connecting Wiring for the 1794-IP4 (using a 1794-TB2, -TB3 or
-TB3S terminal base unit)
1. Connect individual input wiring (N, N) or (D, D) for each channel to
numbered terminals on the 0-15 row (A) as indicated in the table
below.
5. If daisychaining power to the next terminal base, connect a jumper
from terminal 51 (+V dc) on this base unit to terminal 34 on the next
base unit.
6. If continuing dc common to the next base unit, connect a jumper
from terminal 33 (common) on this base unit to terminal 16 on the
next base unit.
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33
16
-V
Common
35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51
34
Voltage
In +V
-V (Supply Common) = Terminals B16 and B33
+V (Supply +Voltage) = Terminals C34 and C51
(Use B33 and C51 for daisy-chaining to next terminal base unit.)
Inputs
Commons
Voltage
A
B
-V
Common
Voltage
Out +V
(1794-TB3 shown)
C
Connecting Wiring for the 1794-IP4 (using a 1794-TBN terminal
base unit)
1. Connect individual input wiring (N, N) or (D, D) for each channel to
the even-numbered terminals on the 16-33 row (B) as indicated in the
table below.
2. Connect the associated input common to the corresponding
odd-numbered terminal on the 34-51 row (C) for each input as
indicated in the table below.
ATTENTION
3. Connect +V dc power to terminal 34 on the 34-51 row (C).
4. Connect dc return to terminal 16 on the 16-33 row (B).
5. If daisychaining power to the next terminal base, connect a jumper
from terminal 51 (+V dc) on this base unit to terminal 34 on the next
base unit.
6. If continuing dc common to the next base unit, connect a jumper
from terminal 33 (common) on this base unit to terminal 16 on the
next base unit.
Do not connect maximum input voltage simultaneously to
all inputs if the module ambient temperature is expected to
exceed 40°C.
If the ambient temperature is expected to continuously
exceed 40°C, you must limit the input voltage using an
external resistor on each input. A 1kW resistor effectively
limits a 24V sensor signal to about 15V at the input. Do not
limit the input to less than 6V.
2. Connect the associated input common to the corresponding terminal
on the 16-33 row (B) for each input as indicated in the table below.
ATTENTION
Do not connect maximum input voltage simultaneously to
all inputs if the module ambient temperature is expected to
exceed 40°C.
If the ambient temperature is expected to continuously
exceed 40°C, you must limit the input voltage using an
external resistor on each input. A 1kΩ resistor effectively
limits a 24V sensor signal to about 15V at the input. Do not
COM
16
34
+V
V = Terminals C34 and C51
OM (-V) = Terminals B16 and B33
4
2
0
1
6789101112
3
5
Odd Numbered I/O Terminals 1 thru 15
COM
14
33
13
15
B
51
C
+V
limit the input to less than 6V.
3. Connect +V dc power to terminal 34 on the 34-51 row (C).
4. Connect dc return to terminal 16 on the 16-33 row (B).
Publication 1794-IN064D-EN-P - March 2005