Allen-Bradley 1794-IA8 Service manual

Installation Instructions
Original Instructions
FLEX I/O AC Digital Input Modules
Catalog Numbers 1794-IA8, 1794-IA8I, 1794-IA16
Topic Page
Important User Information 2
Environment and Enclosure 3
North American Hazardous Location Approval 4
Prevent Electrostatic Discharge 5
Installing Your AC Digital Input Module 7
Configuring Your AC Input Module 14
Specifications 16

2Rockwell Automation Publication 1794-IN102D-EN-P - July 2018
FLEX I/O AC Digital Input Modules
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.rockwellautomation.com/literature/) 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 that are 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, when necessary, 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.
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 and recognize the consequences.
SHOCK HAZARD: Labels may be on or inside the equipment (for example, drive or motor)
to alert people that dangerous voltage may be present.
BURN HAZARD: Labels may be on or inside the equipment (for example, drive or motor) to
alert people that surfaces may reach dangerous temperatures.
IMPORTANT Identifies information that is critical for successful application and understanding of
the product.

Rockwell Automation Publication 1794-IN102D-EN-P - July 2018 3
FLEX I/O AC Digital Input Modules
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 5V A 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,
publication 1770-4.1, for additional installation requirements.
• NEMA Standard 250 and EN/IEC 60529, as applicable, for explanations of the
degrees of protection provided by enclosures.
ATTENTION: Read this document and the documents listed in the Additional
Resources section about installation, configuration, and operation of this
equipment before you install, configure, operate, or maintain this product. Users
are required to familiarize themselves with installation and wiring instructions in
addition to requirements of all applicable codes, laws, and standards.
Installation, adjustments, putting into service, use, assembly, disassembly, and
maintenance are required to be carried out by suitably trained personnel in
accordance with applicable code of practice. In case of malfunction or damage, no
attempts at repair should be made. The module should be returned to the
manufacturer for repair. Do not dismantle the module.

4Rockwell Automation Publication 1794-IN102D-EN-P - July 2018
FLEX I/O AC Digital Input Modules
North American Hazardous Location Approval
The following modules are North American Hazardous Location approved:
1794-IA8, 1794-IA8I, 1794-IA16.
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.
WARNING:
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.
AVERTISSEMENT:
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.
WARNING: When used in a Class I, Division 2, hazardous location, this equipment
must be mounted in a suitable enclosure with proper wiring method that
complies with the governing electrical codes.

Rockwell Automation Publication 1794-IN102D-EN-P - July 2018 5
FLEX I/O AC Digital Input Modules
Prevent Electrostatic Discharge
Special Conditions for Safe Use
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:
• 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. Refer to Industrial Automation Wiring and Grounding Guidelines,
publication 1770-4.1, for more information.
• Do not remove or replace an Adapter Module while power is applied.
Interruption of the backplane can result in unintentional operation or
machine motion.
• Do not remove or replace a terminal base unit while power is applied.
Interruption of the backplane cab result in unintentional operation or
machine motion.
• If this equipment is used in a manner not specified by the manufacturer, the
protection provided by the equipment may be impaired.

6Rockwell Automation Publication 1794-IN102D-EN-P - July 2018
FLEX I/O AC Digital Input Modules
Electrical Safety Considerations
WARNING:
• When you insert or remove the module while backplane power is on, an
electric 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 electric 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 insert or remove the module while backplane power is on, an electric 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 equipment is certified for use only within the surrounding air temperature
range of -20…55 °C (-4…131 °F). The equipment must not be used outside
of this range.
• Use only a soft dry anti-static cloth to wipe down equipment. Do not use any
cleaning agents.
At the end of its life, this equipment should be collected separately from any
unsorted municipal waste.

Rockwell Automation Publication 1794-IN102D-EN-P - July 2018 7
FLEX I/O AC Digital Input Modules
Installing Your AC Digital Input Module
The module mounts on a 1794 terminal base.
1. Rotate the keyswitch (1) on the terminal base (2) clockwise to position 8
as required for this type of module.
2. Ensure that the Flexbus connector (3) is pushed all the way to the left to
connect with the neighboring terminal base/adapter. Yo u c a nn o t i ns t a l l
the module unless the connector is fully extended.
Description Description
1Keyswitch 5Alignmentbar
2Terminalbase 6Groove
3 Flexbus connector 7 Latching mechanism
4Module
ATTENTION: 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.
1
2
3
45
6
7

8Rockwell Automation Publication 1794-IN102D-EN-P - July 2018
FLEX I/O AC Digital Input Modules
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.
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.
Connecting Wiring for the 1794-IA8
1. For 1794-TB2, 1794-TB3, or 1794-TB3S – Connect individual input
wiring to even-numbered terminals on the 0...15 row (A) as indicated in
the Wiring Connections for 1794-IA8 table.
For 1794-TBN – Connect individual input wiring to numbered
terminals on the 16...33 row (B) as indicated in the Wiring Connections
for 1794-IA8 table.
2. For 1794-TB2 – Connect the associated 120V AC power lead (L1) of
the input device to the corresponding odd-numbered terminals on the
0...15 row A for each input as indicated in the Wiring Connections for
1794-IA8 table. (The odd-numbered terminals on row A are internally
connected to 120VAC L1.)
For 1794-TB3 or 1794-TB3S – Connect the associated 120V AC
power lead (L1) of the input device to the corresponding odd-numbered
terminals on the 34...51 row (C) or to the corresponding terminal on
row (C) for each input as indicated in the Wiring Connections for
1794-IA8 table. (The odd-numbered terminals on row (A) and the
terminals of row (C) are internally connected to 120V AC power L1.)
WARNING: If 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.

Rockwell Automation Publication 1794-IN102D-EN-P - July 2018 9
FLEX I/O AC Digital Input Modules
For 1794-TBN – Connect the associated 120V AC power lead (L1) of
the input device to the corresponding odd-numbered terminal on the
34...51 row (C) for each input as indicated in the Wiring Connections
for 1794-IA8 table. (The 120V AC power terminals of row (C) are
internally connected together.)
3. Connect 120V AC power (L1) to terminal 34 on the 34...51 row (C).
4. Connect 120V AC common (L2) to terminal 16 on the 16...33 row (B).
5. If daisychaining power to the next terminal base, connect a jumper from
terminal 51 (+120V AC L1) on this base unit to terminal 34 on the next
base unit.
6. If continuing AC common to the next base unit, connect a jumper from
terminal 33 (120V common L2) on this base unit to terminal 16 on the
next base unit.
Wiring Connections for 1794-IA8
1794-TB2, 1794-TB3, 1794-TB3S 1794-TBN
Input Input Terminal 120V AC Supply Input Terminal 120V AC Supply
Input 0 A-0 A-1(1)/C-35
(1) A-1, 3, 5, 7, 9, 11, 13, and 15 on the 1794-TB2, 1794-TB3, and 1794-TB3S are internally connected in the module to 120V AC L1.
B-0 C-1(2)
(2) C-1, 3, 5, 7, 9, 11, 13, and 15 on the 1794-TBN are internally connected in the module to 120V AC L1.
Input 1 A-2 A-3(1)/C-36 B-2 C-3(2)
Input 2 A-4 A-5(1)/C-37 B-4 C-5(2)
Input 3 A-6 A-7(1)/C-38 B-6 C-7(2)
Input 4 A-8 A-9(1)/C-39 B-8 C-9(2)
Input 5 A-10 A-11(1)/C-40 B-10 C-11(2)
Input 6 A-12 A-13(1)/C-41 B-12 C-13(2)
Input 7 A-14 A-15(1)/C-42 B-14 C-15(2)
A = Input terminals (Even-numbered terminals 0...14)
B = Common terminals
C = Power terminals (C-34 and C-51 on 1794-TB2; C-34 to C-
51 on 1794-TB3 and 1794-TB3S)
B = Even-numbered input terminals 0...14,
AC common terminals 16 and 33
C = Power terminals C-34 and C-51, and
odd-numbered input terminals 1...15

10 Rockwell Automation Publication 1794-IN102D-EN-P - July 2018
FLEX I/O AC Digital Input Modules
1794-TB2, 1794-TB3, and 1794-TB3S Terminal Base Wiring for
1794-IA8 and 1794-IA16
1794-TBN Terminal Base Wiring for 1794-IA8 and 1794-IA16
Connecting Wiring for the 1794-IA16
1. For 1794-TB3 or 1794-TB3S – Connect individual input wiring to
numbered terminals on the 0...15 row (A) as indicated in the Te r m i n a l
Base Wiring for 1794-IA16 table.
For 1794-TBN – Connect individual input wiring to even-numbered
terminals on the 16...33 row (B), and to the odd-numbered terminals on
17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
16
35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51
34
Inputs
Commons
(1794-TB3 shown)
L2
L1 Voltage
A
B
C
L2
Connect 120V AC L1 power to terminal C-34
Connect 120V AC common L2 to terminal B-16
Use B-33 and C-51 for daisychaining to the next terminal base unit
L1
(Terminals C-35 thru C-50 not available on the 1794-TB2.)
16 0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15 51
33
34
L1
L2
L1
L2
B
C
Even Numbered I/O Terminals 0 thru 14
Odd Numbered I/O Terminals 1 thru 15 (1794-TBN shown)
L1 = 120V AC - Connect to terminal C-34
L2 = 120V AC common - Connect to terminal B-16
Use B-33 and C-51 for daisychaining to the next terminal base unit

Rockwell Automation Publication 1794-IN102D-EN-P - July 2018 11
FLEX I/O AC Digital Input Modules
the 34...51 row (C) as indicated in the Terminal Base Wiring for 1794-
IA16 table.
2. For 1794-TB3 or 1794-TB3S – Connect the associated 120V AC
power lead (L1) of the input device to the corresponding terminals on
the 34...51 row (C) for each input as indicated in the Te r m i n a l B a s e
Wiring for 1794-IA16 table. (The 120V power terminals of row (C) are
internally connected together.)
For 1794-TBN – An external terminal strip is needed to distribute
120V AC power (L1) to each device.
3. Connect 120V AC power (L1)to terminal 34 on the 34...51 row (C).
4. Connect 120V AC common (L2) to terminal 16 on the 16...33 row (B).
5. If daisychaining power to the next terminal base, connect a jumper from
terminal 51 (+120V AC L1) on this base unit to terminal 34 on the next
base unit.
6. If continuing AC common to the next base unit, connect a jumper from
terminal 33 (120V common L2) on this base unit to terminal 16 on the
next base unit.
Terminal Base Wiring for 1794-IA16
Input Input Terminal
1794-TB3, 1794-TB3S
Input Terminal
1794-TBN 120V AC Supply (L1)(1)
Input 0 A-0 B-0 C-35
Input 1 A-1 C-1 C-36
Input 2 A-2 B-2 C-37
Input 3 A-3 C-3 C-38
Input 4 A-4 B-4 C-39
Input 5 A-5 C-5 C-40
Input 6 A-6 B-6 C-41
Input 7 A-7 C-7 C-42
Input 8 A-8 B-8 C-43

12 Rockwell Automation Publication 1794-IN102D-EN-P - July 2018
FLEX I/O AC Digital Input Modules
Connecting Wiring for the 1794-IA8I
1. For 1794-TB2, 1794-TB3, or 1794-TB3S – Connect individual input
wiring to even-numbered terminals on the 0...15 row (A) as indicated in
the Wiring Connections for 1794-IA8I table.
For 1794-TBN – Connect individual input wiring to even-numbered
terminals 0...14 on the 16...33 row (B) as indicated in the Wiring
Connections for 1794-IA8I table.
Input 9 A-9 C-9 C-44
Input 10 A-10 B-10 C-45
Input 11 A-11 C-11 C-46
Input 12 A-12 B-12 C-47
Input 13 A-13 C-13 C-48
Input 14 A-14 B-14 C-49
Input 15 A-15 C-15 C-50
120V AC L1 Power terminals C-34 to C-51 (C-34 and C-51 on 1794-TBN) are internally connected
together. Connect 120V AC L1 to C-34.
120V AC L2 Common terminals B-16 to B-33 (B-16 and B-33 for 1794-TBN) are internally connected
together. Connect 120V AC common L2 to terminal B-16.
(1) When using the 1794-TBN, an external terminal strip is needed to connect the 120V AC power connections.
Terminal Base Wiring for 1794-IA16
Input Input Terminal
1794-TB3, 1794-TB3S
Input Terminal
1794-TBN 120V AC Supply (L1)(1)

Rockwell Automation Publication 1794-IN102D-EN-P - July 2018 13
FLEX I/O AC Digital Input Modules
2. For 1794-TB2, 1794-TB3, or 1794-TB3S – Connect the associated
120V AC common (L2) of the isolated supply to the corresponding
odd-numbered terminals on the 0...15 row A for each input as indicated
in the Wiring Connections for 1794-IA8I table.
For 1794-TBN – Connect the associated 120V AC common lead (L2)
of the isolated supply to the corresponding odd-numbered terminal
1...15 on the 34...51 row (C) as indicated in the Wiring Connections for
1794-IA8I table.
IMPORTANT Individual isolated 120V AC L1 power leads must be run externally to
each of the input devices.
Wiring Connections for 1794-IA8I
1794-TB2, 1794-TB3, 1794-TB3S 1794-TBN
Input Input Terminal 120V AC L2
Common Input Terminal 120V AC L2
Common
Input 0 A-0 A-1 B-0 C-1
Input 1 A-2 A-3 B-2 C-3
Input 2 A-4 A-5 B-4 C-5
Input 3 A-6 A-7 B-6 C-7
Input 4 A-8 A-9 B-8 C-9
Input 5 A-10 A-11 B-10 C-11
Input 6 A-12 A-13 B-12 C-13
Input 7 A-14 A-15 B-14 C-15
A = Even-numbered terminals 0...14 for customer
connections; corresponding odd-numbered 120V AC
common L2 terminals 1...15 for customer connections from
isolated power supply.
B = Even-numbered terminals 0...14 for
customer connections;
C = Odd-numbered 120V AC common L2
terminals 1...15 for customer connections
from isolated power supply.

14 Rockwell Automation Publication 1794-IN102D-EN-P - July 2018
FLEX I/O AC Digital Input Modules
1794-TB2, 1794-TB3, and 1794-TB3S Terminal Base Wiring for 1794-IA8I
1794-TBN Terminal Base Wiring for 1794-IA8I
Configuring Your AC Input Module
Image Table Memory Map for the 1794-IA8 and 1794-IA8I Modules
Dec 1514131211109876543210
Oct 17161514131211107 6 5 4 3 2 1 0
Read I7 I6 I5 I4 I3 I2 I1 I0
Write Not used – set to 0 Filter Time FT
0...7
Where I = Input
FT = Input filter time
17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
16
35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51
34
(1794-TB3 shown)
A
B
C
Connect Inputs to even numbered terminals on row (A)
Connect 120V AC common L2 to odd numbered terminals on row (A)
16 0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15 51
33
34
B
C
Even Numbered I/O Terminals 0 thru 14
Odd Numbered I/O Terminals 1 thru 15
(1794-TBN shown)
Connect Inputs to even numbered terminals on row (B)
L2 = 120V AC common - Connect to odd numbered terminals on row (C)

Rockwell Automation Publication 1794-IN102D-EN-P - July 2018 15
FLEX I/O AC Digital Input Modules
Setting the Input Filter Time
You can increase the input filter time (FT) for channels 00...07 (1794-IA8 and
1794-IA8I) and channels 00...15 (1794-IA16) by setting the corresponding bits
in the output image table (complementary word) for the module.
For example, to increase the off-to-on filter time to 12 ms for all inputs at address
rack 1, module group 0, set bits, and program as shown below.
To increase the filter time, set the bits according to the Input Filter Time table.
Image Table Memory Map for the 1794-IA16 Module
Dec 1514131211109876543210
Oct 17161514131211107 6 5 4 3 2 1 0
Read1I15I14I13I12I11I10I9I8I7I6I5I4I3I2I1I0
Write 3 Not used – set to 0 Input Filter FT
12...15
Input Filter FT
0...11
Where I = Input
FT = Input filter time
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
FT = 12-15 FT = 0-11
1794-IA8, 1794-IA8I
1794-IA16
O:010
Dec.
100
76543
FLL
I:000
00
Fill File
Source
Destination
Length
#O:010
1
Write FT to complement
of input module.
Write filter time on system startup.
7654 32 1 0
0
10
= 4 Octal or 4 Decimal
21 0 = 44 Octal or 36 Decimal
010100
1794-IA8
1794-IA16
1794-IA8I

16 Rockwell Automation Publication 1794-IN102D-EN-P - July 2018
FLEX I/O AC Digital Input Modules
Input Filter Time
Specifications
Bits Description
Selected
Filter Time
Maximum
Filter Time
(ms) 1794-
IA8
Maximum
Filter Time
(ms) 1794-
IA8I
Maximum
Filter Time
(ms) 1794-
IA16
02 01 00 Filter Time –
Inputs 00...11 Off
to
On
On
to
Off
Off
to
On
On
to
Off
Off
to
On
On
to
Off
05 04 03 Filter Time –
Inputs 12...15
000Filter time 0
(default) 256 μs 8.4 26.4 8.4 26.4 7.5 26.5
001Filtertime1 512μs 8.6 26.68.6 26.68 27
010Filtertime2 1ms 9 27 9 27 9 28
011Filtertime3 2ms 10 28 10 28 10 29
101Filtertime4 4ms 12 30 12 30 12 31
101Filtertime5 8ms 16 34 16 34 16 35
110Filtertime6 16ms 24 42 24 42 24.544
111Filtertime7 32ms 40 58 40 58 42 60.5
Specifications – 1794-IA8, 1794-IA8I
Attribute 1794-IA8 1794-IA8I
Number of inputs 8, nonisolated 8, isolated
Recommended terminal base unit 1794-TBN, 1794-TB2, 1794-TB3, 1794-TB3S, 1794-TBKD, 1794-
TB3K, 1794-TB3SK, 1794-TBNK
On-state voltage, min 65V AC
On-state voltage, nom 120V AC
On-state voltage, max 132V AC
On-state current, min(1) 7.1 mA

Rockwell Automation Publication 1794-IN102D-EN-P - July 2018 17
FLEX I/O AC Digital Input Modules
On-state current, max 14.32 mA
Off-state voltage, max 43V AC
Off-state current, min 2.9 mA
Nominal input impedance 10.6 kΩ
Nominal input current 12 mA @ 120V AC
Isolation voltage
120V (continuous), Basic
Insulation Type
Type tested @ 1250V AC for 60 s,
between field side and system
No isolation between individual
channels
120V (continuous), Basic
Insulation Type
Type tested @ 1240V AC for 60 s,
between field side and system
Isolation between individual
channels.
Input filter time See Input Filter Time table
Flexbus current 30 mA @ 5V DC
Power dissipation, max 4.5 W @ 132V AC
Thermal dissipation, max 15.3 BTU/hr @ 132V AC
(1) AC inputs compatible with proximity switches with leakage ratings of Ileak < 2.5 mA and Ion minimum = 5 mA
Specifications – 1794-IA16
Attribute Value
Number of inputs 16, nonisolated
Module location 1794-TB3, 1794-TB3S, 1794-TBN(2), 1794-TB3K, 1794-TB3SK,
1794-TBNK
On-state voltage, min 74V AC
On-state voltage, nom 120V AC
On-state voltage, max 132V AC
On-state current, min(1) 5.49 mA
On-state current, max 14.81 mA
Off-state voltage, max 20V AC
Off-state current, min 2.9 mA
Specifications – 1794-IA8, 1794-IA8I
Attribute 1794-IA8 1794-IA8I

18 Rockwell Automation Publication 1794-IN102D-EN-P - July 2018
FLEX I/O AC Digital Input Modules
Nominal input impedance 10 k<Symbol>W
Nominal input current 12 mA @ 120V AC
Isolation voltage
120V (continuous), Basic Insulation Type
Type tested @ 1264V AC for 60 s, between field side and system
No isolation between individual channels
Input filter time See Input Filter Time table
Flexbus current 20 mA
Power dissipation, max 6.4 W @ 132V AC
Thermal dissipation, max 21.8 BTU/hr @ 132V AC
(1) AC inputs compatible with proximity switches with leakage ratings of Ileak < 2.5 mA and Ion minimum = 5 mA
(2) Auxiliary terminal strips are required when using the 1794-TBN.
General Specifications
Attribute 1794-IA8, 1794-IA8I 1794-IA16
Terminal base screw torque Determined by installed terminal base
Dimensions, approx. (H x W x D) 94 x 94 x 69 mm (3.7 x 3.7 x 2.7 in.)
Indicators (field side indication) 8 yellow status indicators 16 yellow status indicators
External AC power supply voltage, nom 120V AC
External AC power voltage range 65...132V AC 74...132V AC
North American temperature code T4A T4
Keyswitch position 8
Enclosure type rating None (open-style)
Wire size Determined by installed terminal base
Wiring category(1) 2 – on signal ports
(1) Use this Conductor Category information for planning conductor routing as described in the appropriate System Level
Installation Manual. Also refer to Industrial Automation Wiring and Grounding Guidelines, publication 1770-4.1, for
more information.
Specifications – 1794-IA16
Attribute Value

Rockwell Automation Publication 1794-IN102D-EN-P - July 2018 19
FLEX I/O AC Digital Input Modules
Environmental Specifications
Attribute 1794-IA8, 1794-IA8I 1794-IA16
Operating temperature
IEC 60068-2-1 (Test Ad, operating cold),
IEC 60068-2-2 (Test Bd, operating dry heat),
IEC 60068-2-14 (Test Nb, operating thermal shock):
-20…55 °C (-4…131 °F) 0…55 °C (32…131 °F)
Storage temperature
IEC 60068-2-1 (Test Ab, unpackaged nonoperating cold),
IEC 60068-2-2 (Test Bb, unpackaged nonoperating dry heat),
IEC 60068-2-14 (Test Na, unpackaged nonoperating thermal shock):
-40…85 °C (-40…185 °F)
Temperature, surrounding air,
max 55 °C (131 °F)
Relative humidity IEC 60068-2-30 (Test Db, Unpackaged Damp Heat):
5…95% noncondensing
Vibration IEC60068-2-6 (Test Fc, Operating):
5 g @ 10...500 Hz
Shock, operating IEC60068-2-27 (Test Ea, Unpackaged shock):
30 g
Shock, nonoperating IEC60068-2-27 (Test Ea, Unpackaged shock):
50 g
Emissions IEC 61000-6-4
ESD immunity
IEC 61000-4-2:
6 kV contact discharges
8 kV air discharges
Radiated RF immunity
IEC 61000-4-3:
10V/m with 1 kHz sine-wave 80% AM from 80…2000 MHz
10V/m with 200 Hz 50% Pulse 100% AM @ 900 MHz
10V/m with 200 Hz 50% Pulse 100% AM @ 1890 MHz
1V/m with 1 kHz sine-wave 80% AM from 2000…2700 MHz

20 Rockwell Automation Publication 1794-IN102D-EN-P - July 2018
FLEX I/O AC Digital Input Modules
EFT/B immunity
IEC 61000-4-4:
±2 kV @ 5 kHz on power ports
±2 kV @ 5 kHz on signal ports
Surge transient immunity IEC 61000-4-5:
±1 kV line-line(DM) and ±2 kV line-earth(CM) on signal ports
Conducted RF immunity IEC 61000-4-6:
10V rms with 1 kHz sine-wave 80% AM from 150 kHz…80 MHz
Certifications
Certifications (When Product
is Marked)(1) Value
c-UL-us
(1794-IA8, 1794-IA8I only)
UL Listed Industrial Control Equipment.
See UL File E65584.
(1794-IA16 only)
UL Listed Industrial Control Equipment, certified for US and Canada.
See UL File E322657.
UL Listed for Class I, Division 2 Group A,B,C,D Hazardous Locations, certified for U.S.
and Canada.
See UL File E334470.
CSA
(1794-IA8, 1794-IA8I only)
CSA Certified Process Control Equipment.
See CSA File LR54689C.
CSA Certified Process Control Equipment for Class I, Division 2 Group A,B,C,D
Hazardous Locations.
See CSA File LR69960C.
CE
European Union 2014/30/EU EMC Directive, compliant with:
• EN 61326-1; Meas./Control/Lab., Industrial Requirements
• EN 61000-6-4; Industrial Emissions
• EN 61131-2; Programmable Controllers (Clause 8, Zone A & B)
European Union 2014/35/EU LVD, compliant with:
• EN 61131-2; Programmable Controllers (Clause 11)
European Union 2011/65/EU RoHS, compliant with:
• EN 50581; Technical documentation
Environmental Specifications
Attribute 1794-IA8, 1794-IA8I 1794-IA16