Guard I/O Introduction

Control and monitor your safety devices with Guard I/O. When used with Rockwell Automation safety controllers, Guard I/O communicates on EtherNet/IP or DeviceNet using CIP Safety protocol. As a proven technology, Guard I/O will detect failures at the I/O and field device level, while enhancing operator protection. Guard I/O are block I/O modules that include the communications adapter and either 8 or 16 points of safety I/O in a single package.

Guard I/O modules on DeviceNet are available in both IP20 (cabinet mount) and IP67 (on-machine) form-factors and Guard I/O modules on EtherNet/IP are available in IP20 form factors.

Guard I/O modules offer the following advantages when implementing a safety control system:

• Reduced engineering — Onboard, Guard I/O has self-diagnostics, hardware testing, and field circuit testing (short-circuit, wire break, discrepancy) with no additional programming required.
  
• Cost-reduced hardware options — Increases ability to safely shutdown an application without additional safety relays.
  
• Space-savings — Monitor and control more safety devices using less panel space.
  
• Use of existing network infrastructures — Connect to standard and safety I/O over one DeviceNet or EtherNet/IP network.
  
• Flexibility and easy migration to EtherNet/IP — The same Guard I/O modules for both DeviceNet and EtherNet/IP networks lets you re-use engineering designs.
  
• Highest safety level — TÜV-certified up to SIL 3/Category 4.
  

	CompactBlock Guard I/O Modules	ArmorBlock Guard I/O Modules
Description	Cost-effective block I/O for use in an enclosure.	Cost-effective block I/O with IP67 protection for use on the machine.
Digital Safety Inputs	Up to 16 channels	Up to 8 channels
Digital Safety Outputs	Up to 8 channels	Up to 4 channels
Safety Relays	Up to 4 channels	No
High Current Capacity Outputs	Up to 2 amps per channel	Up to 2 amps per channel
Use in Hazardous Areas	UL Listed for Class I, Division 2 Group A,B,C,D	No
DeviceNet
Interface Module	1756-DNB, 1753-DNSI, 1752	1756-DNB, 1753-DNSI, 1752
Bulletin Number	1791DS	1732DS
EtherNet/IP
Interface Module	1756-ENBT, 1756-EN2T, 1756-EN2F	Not available
Bulletin Number	1791ES	Not available

Common Guard I/O Module features:

• Integrated pulse test outputs for testing safety circuitry like e-stops and gate switches, for use in applications up to Category 4. These outputs can also be used independently for standard output control or voltage source to sensors.
  
• Safety outputs, with integrated pulse testing for use in applications up to Category 4.
  
• Ability to detect at each I/O point:
  
  • short-circuit to 24V dc or 0V
    
  • wire breakage
    
  • discrepancy of dual channel circuitry, due to mechanical alignment or a failure
    
• All Guard I/O modules have common circuit functionality, operation, programming, troubleshooting, and diagnostics.
  
• Built in diagnostic LEDs for I/O circuitry and power status.
  
• I/O point status available to any controller.
  
• EDS file or Logix 5000 profile compatible.
  
• Removable and keyed terminal blocks.
  
• Common power and I/O wiring across Guard I/O modules on DeviceNet and EtherNet/IP networks (1791DS-IB16/1791ES-IB16 and 1791DS-IB8XOBV4/1791ES-IB8XOBV4).
  
• Safety input power source separate from safety output power source.
  
• Removable and insertable under power, when following appropriate safety practices.
  
• Electronic overcurrent protection of all outputs.
  

Typical Configurations



The above example network shows how almost any 24V dc safety-rated or standard sensor can be wired to any Guard I/O module to monitor the machine’s status.

Choosing Your I/O Hardware

Guard I/O module options are available to minimize associated safety hardware. Additionally, installation costs, wiring time, and commissioning time can be further reduced when using ArmorBlock Guard I/O, as shown in the example below with a light curtain muting application.


A variety of CompactBlock Guard I/O is available to suit most every need.

• 1791DS-IB8XOB8 Module. This module has up to 8 single channel safety inputs and 8 single channel safety outputs. It is often the universally chosen Guard I/O hardware for almost every application. Whether you need single or dual channel safety input or safety output circuits, the 1791DS–IB8XOB8 module is a good choice.
  
• 1791DS-IB4XOW4 Module. This module has up to 4 single channel safety inputs and 4 single channel (replaceable) safety relay outputs. This module is often chosen for AC actuators or specialty safety interface applications. Whether you need single or dual-channel safety input or safety output circuits, the 1791DS-IB4XOW4 module is a good choice.
  
• 1791DS-IB8XOBV4 or 1791ES-IB8XOBV4 Modules. These modules have up to 8 single channel safety inputs and 4 dual channel sink/source safety outputs, also know as bipolar or two-pole switching. They are often chosen for safety actuators that require more than 0.5 amps. For example, the control of press safety valves or control of the solenoid on a guard-locking switch like the Atlas or Trojan safety products. Whether you need single or dual channel safety input circuits and dual channel safety outputs, the 1791DS-IB8XOBV4 or 1791ES-IB8XOBV4 module will suit most any application.
  
• 1791DS-IB16 or 1791ES-IB16 Modules. These modules have up to 16 single channel safety inputs. They are the universal choice of Guard I/O hardware when an application calls for the monitoring of many safety devices in one central location. When your safety application requires 2 safety mats, 2 run stations with 2 e-stops, or any similar configuration, these modules are an excellent and economical choice for every programmable safety system.