Rockwell Automation Allen-Bradley GuardPLC 1753-IB20XOB8 User manual

Installation Instructions
GuardPLC Digital Input/Output
Module
Catalog Number 1753-IB20XOB8
Topic Page
Important User Information 2
About the Module 3
General Safety 3
Install the Module 4
Mount the Module 5
Ground the Module 5
Wire the Module 6
Make Connections for Safety-related
Communication 12
Reset Push Button 12
Status Indicators 13
Specifications 14
Additional Resources 18

2GuardPLC Digital Input/Output Module
Rockwell Automation Publication 1753-IN003C-EN-P - June 2010
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 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.
WARNING: 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.

GuardPLC Digital Input/Output Module 3
Rockwell Automation Publication 1753-IN003C-EN-P - June 2010
About the Module
The 1753-IB20XOB8 digital input/output module is a 28-channel (20 inputs/8 outputs)
module for use with GuardPLC controllers.
General Safety
Preventing Electrostatic Discharge
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.
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 static potential.
•Wear an approved wrist-strap grounding device.
•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.
Digital Outputs
Digital Inputs
Voltage Supply Connection
Ethernet Ports (on bottom of controller)

4GuardPLC Digital Input/Output Module
Rockwell Automation Publication 1753-IN003C-EN-P - June 2010
Environment and Enclosure
Install the Module
Follow these steps to install the module.
1. Mount the module to a DIN rail.
2. Ground the module.
3. Wire the module.
4. Make connections for safety-related communication.
This publication describes these steps in detail.
ATTENTION: 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 m (6562 ft) without derating.
This equipment is considered Group 1, Class A industrial equipment according
to IEC/CISPR 11. Without appropriate precautions, there may be difficulties
with electromagnetic compatibility in residential and other environments due
to conducted as well as radiated disturbances.
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 enclosure must have
suitable flame-retardant properties to prevent or minimize the spread of flame,
complying with a flame spread rating of 5VA, V2, V1, V0 (or equivalent) if
non-metallic. 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.
In addition to this publication, see:
•Industrial Automation Wiring and Grounding Guidelines, Rockwell
Automation publication 1770-4.1, for additional installation requirements.
•NEMA 250 and IEC 60529, as applicable, for explanations of the degrees of
protection provided by different types of enclosure.

GuardPLC Digital Input/Output Module 5
Rockwell Automation Publication 1753-IN003C-EN-P - June 2010
Mount the Module
The module cannot be panel-mounted. Mount the module to a DIN rail by following the steps
below.
1. Hook the top slot over the DIN rail.
2. Insert a flathead screwdriver into the gap
between the housing and the latch and pull
the latch downward.
3. Hold the latch down as you push the housing
back onto the DIN rail.
4. Release the latch to lock the module onto the
rail.
Ground the Module
The module is functionally grounded through its DIN rail connection. A protective earth
ground connection is required and is provided through a separate grounding screw on the upper
left of the housing and marked with the grounding symbol .
You must also provide an acceptable grounding path for each device in your application. For
more information on proper grounding guidelines, refer to the Industrial Automation Wiring
and Grounding Guidelines, publication 1770-4.1.
IMPORTANT For effective cooling, mount the module following these guidelines.
•Mount the module horizontally.
•Provide a gap of at least 100 mm (3.94 in.) above and below the module.
•Select a location where air flows freely or use an additional fan.
•Do not mount the module over a heating device.
TIP To remove the module from the DIN rail, insert a flathead screwdriver into
the gap between the housing and the latch and pull the latch downward as
you lift the module off of the rail.
ATTENTION: This product 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 (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.
DIN Rail
(1) Top Slot
Latch
(3)
(2)

6GuardPLC Digital Input/Output Module
Rockwell Automation Publication 1753-IN003C-EN-P - June 2010
Wire the Module
The following sections describe how to connect the voltage supply and connect the inputs and
outputs.
Connect the Voltage Supply
To comply with CE Low Voltage Directives (LVD) and UL restrictions, you must use either a
Safety Extra Low Voltage (SELV), or a Protected Extra Low Voltage (PELV) power supply to
power this module. A SELV supply cannot exceed 30V rms, 42.4V peak, or 60V DC under
normal conditions and under single-fault conditions. A PELV supply has the same rating and is
connected to protected earth.
The supply voltage is connected via a 4-pin connector that accommodates wire sizes up to
2.5 mm2(14 AWG). You need to connect only one wire to L+ and one wire to L-. Both L+ and
L- terminals are internally connected, so you can daisy-chain 24V DC power from the module to
other devices in the panel by using the remaining terminal.
IMPORTANT Protect the module with a slow-blow fuse.
IMPORTANT The module can draw up to 8 A. The controllers need 0.4 A to operate. Up to
7.6 A can be used to source voltage power for inputs and outputs connected
to the module.
ATTENTION: Do not reverse the L+ and L- terminals or damage to the module
will result. There is no reverse polarity protection.

GuardPLC Digital Input/Output Module 7
Rockwell Automation Publication 1753-IN003C-EN-P - June 2010
Safety-related Digital Inputs
The module has 20 digital inputs (DI1…DI20) whose status is indicated via status indicators.
LS+ is a voltage source that provides 24V DC for a group of four dry contact inputs. There are
five groups on the module.
If devices require 24V DC to operate and use the same power source as the module, then wire the
outputs of the device directly to inputs on the module.
L-L- L+ L+
1LS+ LS+ LS+ LS+ LS+L-
D1
234
13 14 15 16 17 18
5L-
D1
678
19 20 21 22 23 24
9L-
D1
10 11 12
25 26 27 28 29 30
13 L-
D1
14 15 16
31 32 33 34 35 36
17 L-
D1
18 19 20
37 38 39 40 41 42
19 20 21 22 23 2413 14 15 16 23 24
1L- L-DO 2 3 4
(2A)
123456
123456
7L- L-DO 8 9 10
(2A)
789101112
789101112
25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42
24V DC
RUN
24 V DC
PROG
ERROR
FAULT
FORCE
BL
OSL
GuardPLC Ethernet
10/100 BaseT
1(—) 2
(—)
1753-IB20OXB8
20 DC Inputs
8 DC Outputs
1LS+- L-
D1
234
13 14 15 16 17 18
13 14 15 16 23 24
L-L- L+ L+
24V DC
24VDC
Power
Supply
COM
+
Connection of Voltage
Supply to Input Device
L-L- L+ L+
1LS+ LS+ LS+ LS+ LS+L-
D1
234
13 14 15 16 17 18
5L-
D1
678
19 20 21 22 23 24
9L-
D1
10 11 12
25 26 27 28 29 30
13 L-
D1
14 15 16
31 32 33 34 35 36
17 L-
D1
18 19 20
37 38 39 40 41 42
19 20 21 22 23 2413 14 15 16 23 24
1L- L-DO 2 3 4
(2A)
123456
123456
7L- L-DO 8 9 10
(2A)
789101112
789101112
25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42
24V DC
RUN
24 V DC
PROG
ERROR
FAULT
FORCE
BL
OSL
GuardPLC Ethernet
10/100 BaseT
1
(—)
2
(—)
1753-IB20OXB8
20 DC Inputs
8 DC Outputs
1LS+- L-
D1
234
13 14 15 16 17 18
13 14 15 16 23 24
L-L- L+ L+
24V DC
COM
24VDC
Power
Supply
COM
+
+
Light Curtain
(or any Safety Input)
Connection of Voltage Supply
to Input Device

8GuardPLC Digital Input/Output Module
Rockwell Automation Publication 1753-IN003C-EN-P - June 2010
Devices with their own dedicated power supply can also be connected. Connect the reference
pole of the external power supply to the L- reference pole of the input.
The safe state of an input is indicated by a 0 signal being passed to the user program. If the test
routines detect a fault in the digital inputs, a 0 signal is processed in the user program for the
defective channel. When a fault occurs, the inputs are switched off (0) and the FAULT indicator
is activated.
Follow the closed-circuit principle for external wiring when connecting sensors. To create a safe
state in the event of a fault, the input signals revert to the de-energized state (0). Although the
external line is not monitored, a wire break is interpreted as a safe 0 signal.
Digital Input Terminals
Terminals accommodate wires up to 1.5 mm2(16 AWG). See the terminal torque specifications
on page 14. Digital inputs (DI) are connected to these terminals.
Terminal Number Designation Function
13 LS+ Sensor supply for inputs 1…4
14 1 Digital input 1
15 2 Digital input 2
16 3 Digital input 3
17 4 Digital input 4
18 L- Reference pole
L-L- L+ L+
1LS+ LS+ LS+ LS+ LS+L-
D1
234
13 14 15 16 17 18
5L-
D1
678
19 20 21 22 23 24
9L-
D1
10 11 12
25 26 27 28 29 30
13 L-
D1
14 15 16
31 32 33 34 35 36
17 L-
D1
18 19 20
37 38 39 40 41 42
19 20 21 22 23 2413 14 15 16 23 24
1L- L-DO 2 3 4
(2A)
123456
123456
7L- L-DO 8 9 10
(2A)
789101112
789101112
25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42
24V DC
RUN
24 V DC
PROG
ERROR
FAULT
FORCE
BL
OSL
GuardPLC Ethernet
10/100 BaseT
1
(—)
2
(—)
1753-IB20OXB8
20 DC Inputs
8 DC Outputs
15
L-L- L+ L+
24V DC
24VDC
Power
Supply
COMCOM
+
24VDC
Power
Supply
COM
+
+
Light Curtain
(or any Safety Input)
1LS+- L-
D1
234
13 14 15 16 17 18
13 14 15 16 23 24
Connection of Devices with Dedicated
Power Supplies
1LS+- LS+LS+LS+LS+L-
DI
234
13 14 15 16 17 18
5L-
DI
678
19 20 21 22 23 24
9L-
DI
10 11 12
25 26 27 28 29 30
13 L-
DI
14 15 16
31 32 33 34 35 36
17 L-
DI
18 19 20
37 38 39 40 41 42
19 20 21 22 23 2413 14 15 16 17 18 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42

GuardPLC Digital Input/Output Module 9
Rockwell Automation Publication 1753-IN003C-EN-P - June 2010
LS+, not L+, should be used for short-circuit protection. Each LS+ features individual
short-circuit and EMC protection that make it important to use LS+ for only its four related
inputs.
19 LS+ Sensor supply for inputs 5…8
20 5 Digital input 5
21 6 Digital input 6
22 7 Digital input 7
23 8 Digital input 8
24 L- Reference pole
25 LS+ Sensor supply for inputs 9…12
26 9 Digital input 9
27 10 Digital input 10
28 11 Digital input 11
29 12 Digital input 12
30 L- Reference pole
31 LS+ Sensor supply for inputs 13…16
32 13 Digital input 13
33 14 Digital input 14
34 15 Digital input 15
35 16 Digital input 16
36 L- Reference pole
37 LS+ Sensor supply for inputs 17…20
38 17 Digital input 17
39 18 Digital input 18
40 19 Digital input 19
41 20 Digital input 20
42 L- Reference pole
Terminal Number Designation Function

10 GuardPLC Digital Input/Output Module
Rockwell Automation Publication 1753-IN003C-EN-P - June 2010
Line Control
Line control is a short-circuit and line-break monitoring system, for example, E-stop inputs that
can be configured for the GuardPLC system. Up to eight digital outputs (DO1…DO8) can be
configured as pulsed outputs. The example below shows two pulse outputs connected to the
digital inputs (DI) of the same system. As a result, the connections to the digital inputs (DI) are
monitored.
Inputs are set to 0, a fault code is generated, and the FAULT status indicator is on when:
•a short-circuit occurs between two parallel connections.
•two connections are reversed.
•earth fault occurs on one of the lines (only with earthed reference pole).
•a line breaks or one of the contacts opens (that is, when one of the E-stop off switches is
pressed in the example above).
Safety-related Digital Outputs
The module has eight digital outputs (DO1…DO8) whose status is indicated via status
indicators.
An output is in a safe state when it is de-energized. If a fault occurs, all outputs are turned off.
Outputs 1…3 and 5…7 can have a load of 0.5 A at an ambient temperature of 60 °C (140 °F).
Outputs 4 and 8 can each have a load of 1 A at an ambient temperature of 60 °C (140 °F), or up
to 2 A at an ambient temperature of 50 °C (122 °F).
With an overload, one or all of the outputs are turned off. When the overload is eliminated, the
outputs are activated again according to the specified value.
Although the external line of an output is not monitored, a short-circuit will be indicated.
IMPORTANT For information on how to configure inputs and outputs for line control, see the
GuardPLC Controller Systems User Manual, publication 1753-UM001.
Emergency OFF 1 Emergency OFF 2
DO 1 2
DI 1 2 DI 3 4