Controllogix digital safety i/o modules (136 pages)
Summary of Contents for Allen-Bradley 1756-L7 Series
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Safety Reference Manual Using ControlLogix in SIL 2 Applications Catalog Numbers 1756-L6x, 1756-L7x Allen-Bradley Motors...
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IMPORTANT Identifies information that is critical for successful application and understanding of the product. Allen-Bradley, Rockwell Software, Rockwell Automation, TechConnect, ControlLogix, ControlLogix-XT, GuardLogix, FLEX, RSLogix, Logix5000, RSNetWorx, FactoryTalk, Data Highway Plus, and SynchLink are trademarks of Rockwell Automation, Inc. Trademarks not belonging to Rockwell Automation are property of their respective companies.
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Added information on the restrictions and requirements for changing parameters via an HMI Updated reaction time example calculations Appendix A Updated and moved the list of SIL 2 certified components Appendix B Allen-Bradley Motors This list now includes FLEX I/O modules Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
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Summary of Changes Change Page Updated publication links in the components appendix Appendix B Updated Probability of Failure on Demand (PFD) calculations, including data for 1794 Appendix C FLEX I/O modules, are now in the appendix. All checklists are now in an appendix Appendix D Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
Redundant Power Supplies ........33 Recommendations for Using Power Supplies....34 Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
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Table of Contents Chapter 4 ControlLogix Communication Introduction to Communication Modules ......35 ControlNet Modules and Components ......36 Modules ControlNet Cabling .
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Reading Parameters in Safety-related Systems ....91 Changing Safety-related Parameters in SIL-rated Systems ..92 Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
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Table of Contents Appendix A Reaction Times of the ControlLogix Local Chassis Configuration ........95 Remote Chassis Configuration .
The probability of a system to have a dangerous failure occur per hour. Hour Safety Integrity Level A discrete level for specifying the safety integrity requirements of the safety functions allocated to the electrical/electronic/ programmable electronic (E/E/PE) part of the safety system. Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
In addition to the manuals listed, you may want to reference installation instructions listed in Appendix You can view or download publications at http:/www.rockwellautomation.com/literature/. To order paper copies of technical documentation, contact your local Allen-Bradley® distributor or Rockwell Automation sales representative. Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
All of the examples related to I/O included in this manual are based on achieving de-energization as the safe state for typical Emergency Shutdown (ESD) Systems. Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
Chapter 1 SIL Policy Programming and Debugging Tool (PADT) For support in creation of programs, the PADT (Programming and Debugging Tool) is required. The PADT for ControlLogix is RSLogix 5000, per IEC 61131-3, and this Safety Reference Manual. For more information about programming a system by using pre-developed subroutines or Add-On Instructions, see these publications: •...
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• Any time a fault is detected, the system must annunciate the fault to an operator by some means (for example, an alarm light). Figure 1 - Manual Override Circuit Manual Override Actuator L2 or Ground 43379 Fault Alarm to Operator Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
Chapter 1 SIL Policy Boiler and Combustion Considerations If your SIL 2-certified ControlLogix system is used in combustion-related applications, you are responsible for meeting National Fire Protection Association (NFPA) standard NFPA 85 or NFPA 86. A few failures in ControlLogix SIL2 may take up to eight hours to detect, therefore eight hours is the worst case reaction time.
The SIL 2 portion of the certified system excludes the development tools and display/human machine interface (HMI) devices; these tools and devices must not be part of the safety loop. Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
Chapter 1 SIL Policy Simplex Configuration In a simplex configuration, the hardware used in the safety loop is programmed to fail to safe. The failure to safe is typically an emergency shutdown (ESD) where outputs are de-energized. Figure Figure 4, and Figure 5 show a typical simplex SIL loop.
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ControlNet To other safety related ControlLogix or FLEX I/O remote I/O chassis. Allen-Bradley Motors Note 1: Multiple 1756-CNB or -CNBR modules can be installed into the chassis as needed. Other configurations are possible as long as they are SIL2 approved.
Chapter 1 SIL Policy Duplex Logic Solver Configurations In duplex configurations, redundant system components are used to increase the availability of the control system. The modules in the redundant controller chassis include redundancy modules and network communication modules for redundant communication, as well as the ControlLogix controllers. SIL 2 I/O modules in the safety loop must meet the requirements specified in Chapter ControlLogix I/O...
Chapter 1 SIL Policy Figure 8 - Duplex System ControlNet Configuration SIL 2-certified ControlLogix Safety Loop Secondary Chassis Primary Chassis ControlNet I/O Chassis A I/O Chassis B DC OUTPUT DC INTPUT ANALOG INTPUT DC OUTPUT ANALOG INTPUT DC INTPUT DC INTPUT ANALOG INTPUT ANALOG INTPUT DC INTPUT...
For more information on switchovers in ControlLogix redundancy systems and ControlLogix redundancy systems in general, see these redundancy system manuals: • ControlLogix Standard Redundancy System User Manual, publication 1756-UM523 • ControlLogix Enhanced Redundancy System User Manual, publication 1756-UM535 Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
Chapter 1 SIL Policy Reaction Times The response time of the system is defined as the amount of time it takes for a change in an input condition to be recognized and processed by the controller’s logic program, and then to initiate the appropriate output signal to an actuator. The system response time is the sum of the following: •...
SIL certification. If a product has achieved agency certification, it is marked on the product label. To view additional safety certifications for products, go to http://www.ab.com and click the Product Certifications link. Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
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Chapter 1 SIL Policy Notes: Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
For example, the system can be programmed to retrieve the fault code of the failed module and make a determination, based on the type of fault, Allen-Bradley Motors as to whether to continue operating. Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
Chapter 2 Features of the ControlLogix SIL 2 System This ability of the controller to monitor the health of I/O modules in the system and take appropriate action based on the severity of a fault condition gives the user complete control of the application’s behavior. It is your responsibility to establish the course of action appropriate to your safety application.
– remove the controller key from the keyswitch. • Authorized personnel may change an application program, but only by using one of the processes described in Changing Your Application Program on page Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
Chapter 2 Features of the ControlLogix SIL 2 System Communication Several communication options are available for connecting with the ControlLogix SIL 2 system and for the exchange of data within the SIL 2 system. Communication Ports A built-in serial port is available on 1756-L6x controllers for download or visualization purposes only.
For more information about electronic keying, see the ControlLogix Digital I/O Modules User Manual, publication 1756-UM058. Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
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Chapter 2 Features of the ControlLogix SIL 2 System Notes: Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
The ControlLogix controller consists of a central processor, I/O interface, and memory. Operating Modes The controller performs power-up and run-time functional tests. The tests are used with user-supplied application programs to verify proper controller operation. Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
Chapter 3 ControlLogix Controllers, Chassis, and Power Supplies A three-position keyswitch on the front of the controller governs ControlLogix system operational modes. The following modes are available: • Run • Program • Remote - This software-enabled mode can be Program or Run. Figure 10 - Keyswitch in Run Mode Logix557x FORCE SD...
1756-Px75R power supplies, in that chassis. In this case, we recommend that you use the Series B version of the nonredundant power supplies, that is, the 1756-Px75/B power supplies. Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
Chapter 3 ControlLogix Controllers, Chassis, and Power Supplies Recommendations for Using Power Supplies When using SIL 2-certified ControlLogix power supplies: • follow the information provided in the product’s installation instructions. • a power supply can be used if it meets the user-defined PFD criteria. •...
(1) Not for use in safety functions. ControlLogix communication modules can be used in peer-to-peer communication between ControlLogix devices. The communication modules can also be used for expansion of I/O to additional ControlLogix remote I/O chassis. Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
Chapter 4 ControlLogix Communication Modules ControlNet Modules and The ControlNet bridge modules (catalog numbers 1756-CNB, 1756-CNBR, 1756-CN2, 1756-CN2R, and 1756-CN2RXT) provide communication Components between any nodes properly scheduled on the ControlNet network. ControlNet Cabling For remote racks, a single RG6 coax cable is required for ControlNet communication.
• Non-SIL 2 devices should not write data to SIL 2 controllers. The only exception to this is the use of HMI devices. For more information on how to use HMI in the safety loop, see Chapter Use of Human-to-Machine Interfaces on page Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
Chapter 4 ControlLogix Communication Modules Peer-to-Peer Communication Peer-to-peer communication via a ControlNet or EtherNet/IP network is permitted when these requirements are met: Requirements • Non-SIL 2 controllers can read data from SIL 2 controllers by directly reading the data or by consuming data from a SIL 2 controller that is configured to produce data.
SIL 2-certified ControlLogix I/O modules. This figure shows the SIL 2-certified ControlLogix I/O modules. Each type, digital or analog, is described in greater detail throughout the rest of this chapter. Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
Chapter 5 ControlLogix I/O Modules Application logic is used to compare input values for concurrence. Figure 13 - Logic Comparing Input Values or States Input A Input B No Faults Actuator The user program must also contain rungs to annunciate a fault in the event of a sustained miscompare between two points.
Output Timer Done Fault Fault Alarm to Operator The control, diagnostics and alarming functions must be performed in sequence. For more information on faults, see Chapter Faults in the ControlLogix System. Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
Chapter 5 ControlLogix I/O Modules • Use of external relays to disconnect module power if output de-energized state is critical. To verify that outputs will de-energize, users must wire an external relay or other measure, that can remove power from the output module if a short or other fault is detected.
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• Write logic to test the output’s ability to turn ON and OFF at powerup. • At the proof test interval, force the output ON and OFF and use a voltmeter to verify output performance. Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
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Chapter 5 ControlLogix I/O Modules Automatic testing of output modules (that is, the user turns the outputs ON and OFF to verify proper operation) should be made at intervals that are an order of magnitude less than the safety demand rate. For example, output testing should be scheduled at least twice a year for a low demand system.
Field signal levels should be varied over the full operating range to make sure that the corresponding channel data varies accordingly. For more information, see Proof Tests on page Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
Chapter 5 ControlLogix I/O Modules Calibrate Inputs Analog input modules should be calibrated periodically, as their use and application requires. ControlLogix I/O modules ship from the factory with a highly accurate level of calibration. However, because each application is different, you are responsible for making sure your ControlLogix I/O modules are properly calibrated for your specific application.
When using identical modules, configure the modules identically, that is, by using the same RPI, filter values, and so on. When using different modules for improved diversity, make sure the module’s scaling of data does not introduce error or fault conditions. Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
Chapter 5 ControlLogix I/O Modules Specify the Same Controller as the Owner The same controller must own both analog input modules. You must use Analog Inputs Faulted as a safety status/permissive in respective safety-related outputs. Wiring ControlLogix Analog Input Modules In general, good design practice dictates that each of the two transmitters must be wired to input terminals on separate modules such that the channel values may be validated by comparing the two within an acceptable range.
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Use the same channel on each module to make sure of consistent temperature readings. Figure 24 on page 52 shows how to wire the 1756-IT6I module. Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
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Chapter 5 ControlLogix I/O Modules Figure 24 - ControlLogix Analog Thermocouple Module Wiring Ch0 + Ch0 + Thermocouple A Thermocouple B 43370 Wiring the RTD Input Module Make sure you: • review the considerations in Using Analog Input Modules on page •...
Chapter 5 ControlLogix I/O Modules Using Analog Output There are a number of general application considerations that you must make when using analog output modules in a SIL 2 application. Modules A single analog output module, along with an analog input module for monitoring is required to achieve SIL 2.
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If the monitoring input value and the Output Echo miscompare for longer than the preset value, a fault is registered with a corresponding alarm. Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
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Chapter 5 ControlLogix I/O Modules Figure 27 - Monitoring an Analog Output with an Analog Input Outputs OK Timer MULT Range Delta Delta Tolerance% Monitoring input Monitoring input Delta High Limit Low Limit Low Limit Outputs OK Output Echo High Limit Fault Secondary Output...
(each module output is 250 Ω). Figure 29 on page 58 shows how to wire the 1756-OF8 module for use in Current mode. Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
Chapter 5 ControlLogix I/O Modules Figure 29 - ControlLogix Analog Output Module Wiring in Current Mode This normally-open relay is controlled by the status of the rest of the ControlLogix Analog Output Module Analog Input Module system. If a short-circuit or fault occurs on the module, the relay can disconnect power to the module.
• use the correct documentation (listed in Appendix B) as a reference when wiring the module. Figure 30 - HART Output Analog Module Wiring Actuator Ch0 + Ch0 + Ch0 - Ch0 - Actuator Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
• Wire sensors to separate input points on two separate modules that are on different network nodes. • Configuration parameters (for example, RPI, filter values) must be Allen-Bradley Motors identical between the two modules. Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
Chapter 6 FLEX I/O Modules • The same controller must own both modules. • Monitor the network status bits for the associated module and ensure that appropriate action is invoked via the application logic by these status bits. Wiring FLEX I/O Digital Input Modules The wiring diagrams in Figure 31 show two methods of wiring the digital input...
• Wire sensors to separate input points on two separate modules that are on different network nodes. • Monitor the network status bits for the associated module and make sure that appropriate action is invoked via the application logic by these status bits. Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
Chapter 6 FLEX I/O Modules Wiring FLEX I/O Digital Output Modules When using standard output modules, you must wire an output to an actuator and then back to an input to monitor the output’s performance. Figure 35 - FLEX I/O Standard Output Module Wiring Standard Digital Output Module Wire output point to input Standard Digital Input Module...
Validation test must be performed. Manually, or automatically, test inputs to make sure that all inputs are operational. Field signal levels should be varied over the full operating range to make sure that the corresponding channel data varies accordingly. Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
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Chapter 6 FLEX I/O Modules • Calibrate inputs periodically, as necessary. FLEX I/O modules ship from the factory with a highly accurate level of calibration. However, because each application is different, you are responsible for making sure their FLEX I/O modules are properly calibrated for their specific application.
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• Monitor the network status bits for the associated module and make sure that appropriate action is invoked via the application logic by these status bits. • Wire sensors to separate input channels on two separate modules that are on different network nodes. Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
Chapter 6 FLEX I/O Modules Wiring FLEX I/O Analog Input Modules The wiring diagrams in this section show two methods of wiring the analog input module. In either case, you must determine whether the use of 1 or 2 sensors is appropriate to fulfill SIL2 requirements.
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Figure 40 - FLEX I/O Analog Input Wiring in Current Mode 1794-IE8 Analog Input Analog Input 1794-IE8 1794-IE8 1794-TB3 1794-TB3 Current Current Source A Source B Analog Input Analog Input 1794-IF4I 1794-IF4I 1794-TB3 1794-TB3 Current Current Source B Source A Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
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Chapter 6 FLEX I/O Modules Wiring the Thermocouple Input Module In addition to following the Requirements When Using FLEX I/O Analog Input Modules on page 65 and before wiring the module, consider the following application guideline: • Wire to the same input channel on both modules. When wiring thermocouples, wire two in parallel to two modules.
ESD command and are therefore not recommended for use ESD output modules. The use of digital output modules and actuators to achieve the ESD de-energized state is recommended. Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
Chapter 6 FLEX I/O Modules Requirements When Using FLEX I/O Analog Output Modules Follow these general application considerations when applying the analog output modules in a SIL2 application: • Proof tests - Periodically (for example, once every several years) a System Validation test must be performed.
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They must not share the same FLEX adapter. • Monitor the network status bits for the associated module and make sure that appropriate action is invoked via the application logic by these status bits. Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
Chapter 6 FLEX I/O Modules Wiring FLEX I/O Analog Output Modules In general, good design practice dictates that each analog output must be wired to a separate input terminal to make sure that the output is functioning properly. Wiring the Analog Output Module in Voltage Mode You must wire analog outputs to an actuator and then back to an analog input to monitor the output performance.
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Figure 45 - Analog Output Wiring Example 1794-OE4 1794-IE8 Analog Input Analog Output Module Module 1794-TB3 1794-TB3 Actuator 1794-OF4I 1794-IF4I Isolated Analog Isolated Analog Output Module Input Module 1794-TB3 1794-TB3 Actuator Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
• user application code (user program) uses common and good design practices. • a test plan is documented and adhered to, including well-understood proof test requirements and procedures. • a well-designed validation process is defined and implemented. Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
Chapter 7 Requirements for Application Development For the initial start-up of a safety-related ControlLogix system, the entire system must be checked by a complete functional test. After a modification of the application program, the modified program or logic must be checked. For more information on how users should handle changes to their application program, see Changing Your Application Program on page...
The requirements of the safety and application standards regarding the protection against manipulations must be observed. The authorization of employees and the necessary protection measures are the responsibility of the individuals starting and maintaining the SIL 2 safety system. Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
Chapter 7 Requirements for Application Development Basics of Application The application program is intended to be developed by the system integrator and/or user. The developer must consider general procedures for programming Program Development and ControlLogix SIL 2 applications listed below (this does not require independent Testing third party review).
Logic and Instructions The logic and instructions used in programming the application must be: • easy to understand. • easy to trace. • easy to change. • easy to test. • well-documented. Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
Chapter 7 Requirements for Application Development Program Language You must implement simple, easy to understand: • ladder. • other IEC 61131-3-compliant language. • function blocks with specified characteristics. We use ladder, for example, because it is easier to visualize and make partial program changes with this format.
6. Save the compare results as part of the verification process. 7. Delete the upload file. 8. Rename the original project file (change back) to the original project name to maintain project documentation. Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
Chapter 7 Requirements for Application Development Figure 47 shows the steps required during application program development, Commissioning Life Cycle debugging and commissioning. Figure 47 - Application Development Life Cycle Generate Functional Specification Create Flow Diagram Create Timing Diagrams Establish Sequence of Operations Develop Project Develop Project...
(controller is in Run mode), you cannot make online edits. • You can edit the relay ladder logic portion of the safety program using one of the following methods described in Table Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
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Chapter 7 Requirements for Application Development Table 3 - Methods of Changing Your Application Program in RSLogix 5000 Software Method Required Steps Controller Key Points to this Method Keyswitch Position Offline Perform the tasks described in the flow chart in Figure 47 on page PROG You must re-validate the entire application...
To help handle faults, make sure you have completed the input (see Checklist for SIL Inputs on page 122) and output (see Checklist for SIL Outputs on Allen-Bradley Motors page 124) checklists for their application. Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
Chapter 8 Faults in the ControlLogix System Module Fault Reporting for You must verify that all components in the system are operating properly. This can be accomplished in ladder logic through the use of the Get System Value Any ControlLogix or FLEX I/O instruction (GSV) and an examination of the MODULE Object’s Entry Status’...
High Alarm, the alarm bit is set and a fault is declared. It is your responsibility to determine appropriate behavior when a fault is present. Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
Chapter 8 Faults in the ControlLogix System Additional Resources The ControlLogix architecture provides the user many ways of detecting and reacting to faults in the system. Various device objects can be interrogated to determine the current operating status. Additionally, modules provide run-time status of their operation and of the process.
To avoid safety-related nuisance trips, use good communication practices to limit the impact of communication processing on the controller. Do not set read rates to the fastest rate possible. Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
Chapter 9 Use of Human-to-Machine Interfaces Changing Safety-related Parameters in SIL-rated Systems A parameter change in a safety-related loop via an external (that is, outside the safety loop) device (for example, an HMI) is allowed only with the following restrictions: •...
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HMI and limits access to required data points only. • Similar to the controller program, the HMI software needs to be secured and maintained for SIL-level compliance after the system has been validated and tested. Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
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Chapter 9 Use of Human-to-Machine Interfaces Notes: Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
• The output module processes data from the controller and turns the output device on or off. Figure 51 - Local Chassis Configuration of Digital or Analog Modules Input Module Controller Output Module Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
Appendix A Reaction Times of the ControlLogix System Remote Chassis Figure 52 shows an example system where the following occurs: • Input data changes on the input module. Configuration • The data is transmitted to the controller via the network communication modules.
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• If the safe state in your application is high, use the Off -> On Input Filter Time. Figure 53 - Digital Module Configuration Module RPI is configurable via the Connection tab. Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
Appendix A Reaction Times of the ControlLogix System For Analog Modules Use this formula to determine worst-case reaction time for analog modules in local or remote configurations: Worst-Case Reaction Time with no faults or errors = (Real Time Sample (RTS) Rate) + (Input Module RPI x 4/8/16…...
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(2) Existing systems that use the 1756-PSCA and 1756-PSCA2 are SIL 2-certified. However, when implementing new SIL 2-certified systems or upgrading existing systems, we recommend that you use the 1756-PSCA2 module if possible. Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
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Appendix B SIL 2-certified ControlLogix System Components Table 6 - SIL 2-certified ControlLogix Components - 1756 Nonredundant Controllers, I/O, and Communication Modules Related Cat. No. Description Documentation 1756-L61 ControlLogix 2 MB controller 1756-L62 ControlLogix 4 MB controller 1756-L63 ControlLogix 8 MB controller 1756-L71 ControlLogix 2 MB controller 1756-UM001...
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(6) The 1756-SYNCH module is included in this table because this module can be used to propagate time between chassis and to record events that occur in each chassis. Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
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Appendix B SIL 2-certified ControlLogix System Components Table 7 - SIL 2-certified ControlLogix Components - 1756 Redundancy System Components Related Cat. No. Description Documentation 1756-L61 ControlLogix 2 Mb Controller 1756-L62 ControlLogix 4 Mb Controller 1756-L63 ControlLogix 8 Mb Controller 1756-L71 ControlLogix 2 MB Controller 1756-UM001 1756-L72...
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Appendix B SIL 2-certified ControlLogix System Components Table 9 - FLEX I/O Components For Use in the SIL 2 System Cat. No. Description Related Documentation 1794-OB16PXT FLEX I/O-XT 16 Protected Output Module 1794-IN124 1794-OB8EP FLEX I/O 8 Protected Output Module 1794-IN094 1794-OB8EPXT FLEX I/O-XT 8 Protected Output Module...
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(1) Certain catalog numbers have a K suffix. This indicates a conformally coated version of the product. These K versions have the same SIL2 certification as the non-K versions. (2) These publications are available from Rockwell Automation by visiting http://literature.rockwellautomation.com. Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
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Appendix B SIL 2-certified ControlLogix System Components Notes: Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
The PFD values in this manual are calculated with formulas explained in IEC 61508, Part 6, Annex B. Refer to IEC 61508, Part 6, for more information about calculating PFD values for your system. Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
Appendix C PFD Calculations for a SIL 2 System Determine Which PFD Values To Use You are responsible for determining which PFD values provided are IMPORTANT appropriate for your SIL 2-certified system. Determine which values to use based on the modules used your system and the system configuration. Each of the PFD calculated values provided in this manual is based on the configuration that the module can be used in, that is 1oo1 or 1oo2.
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Appendix C PFD Calculations for a SIL 2 System Table 10 - PFD Calculations - 1-year for ControlLogix Component Calculated PFD 61508 Mean Time Between (10) λ (1) (2) Cat. No. Description 1oo1 1oo2 (2010) Failure (MTBF) Architecture Architecture 1756-IH16ISOE ControlLogix sequence of events module 2,150,720 4.650E-07...
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(8) Calculations for the redundant power supply are completed with the presumption that both power supplies fail simultaneously. (9) MTBF measured in hours. The values used here represent values available in January 2012. (10) λ = Failure Rate = 1/MTBF. Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
Appendix C PFD Calculations for a SIL 2 System 2-Year PFD Calculations The PFD calculations in Table 11 are calculated for a 2-year proof test interval and are specific to ControlLogix system components. Table 11 - PFD Calculations - 2-year for ControlLogix Component Calculated PFD 61508 Mean Time Between...
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Appendix C PFD Calculations for a SIL 2 System Table 11 - PFD Calculations - 2-year for ControlLogix Component Calculated PFD 61508 Mean Time Between (10) λ (1) (2) Cat. No. Description 1oo1 1oo2 (2010) Failure (MTBF) Architecture Architecture 1756-OF6CI ControlLogix isolated analog output module 8,354,667 1.197E-07...
6.379E-08 6.9886E-05 — 1756-PB75R ControlLogix DC redundant power supply 1,736,020 5.760E-07 6.3104E-04 — 1756-PAXT ControlLogix-XT AC power supply 18,693,044 5.350E-08 4.0122E-08 — Allen-Bradley Motors 1756-PBXT/B ControlLogix-XT DC power supply 1,855,360 5.390E-07 5.9045E-04 — Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
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Appendix C PFD Calculations for a SIL 2 System Table 12 - PFD Calculations - 5-year for ControlLogix Component Calculated PFD: 61508 Mean Time Between (10) λ (1) (2) Cat. No. Description 1oo1 1oo2 (2010) Failure (MTBF) Architecture Architecture 1756-PC75/B ControlLogix DC power supply 5,894,836 1.696E-07...
ControlLogix 2 MB controller 1,000,053 2.1949E-04 1756-OB16D DC output module 8,884,374 1.39367-07 1756-IB16D DC diagnostic input module 30,228,640 1.39206E-07 Allen-Bradley Motors Total PFD calculation for a safety loop consisting of these products: 2.2946E-04 Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
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Appendix C PFD Calculations for a SIL 2 System Notes: Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
Have you taken into consideration the checklists for using SIL inputs and outputs listed on pages and 124. (1) For more information on the specific tasks in this checklist, see the previous sections in the chapter or Chapter SIL Policy on page Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
Appendix D Checklists Checklist for SIL Inputs The following checklist is required for planning, programming and start up of SIL inputs. It may be used as a planning guide as well as during proof testing. If used as a planning guide, the checklist can be saved as a record of the plan. For programming or start-up, an individual checklist can be filled in for every single SIL input channel in a system.
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When wiring thermocouple modules in parallel, have you wired to the same channel on each module as shown in Figure 24 on page When wiring two RTD modules, are two sensors used, as shown in Figure 25 on page Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
Appendix D Checklists Checklist for SIL Outputs The following checklist is required for planning, programming and start up of SIL outputs. It may be used as a planning guide as well as during proof testing. If used as a planning guide, the checklist can be saved as a record of the plan. For programming or start-up, an individual requirement checklist must be filled in for every single SIL output channel in a system.
Was all force information reset before safety operation? Has it been verified that the system is operating properly? Have the appropriate security routines and functions been installed? Is the controller keyswitch in Run mode and the key removed? Allen-Bradley Motors Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
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Appendix D Checklists Notes: Rockwell Automation Publication 1756-RM001I-EN-P - May 2012...
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