Release Notes

ControlLogix Controllers
Version 34.013 (released 7/2023)

Catalog Number 1756-L75 (series B)

These release notes describe version information for 1756-L75, version 34.013 (released 7/2023).

Security

This release includes security enhancements as a part of our ongoing efforts to improve security. For information regarding Rockwell Automation's vulnerability disclosure process, please reference the Rockwell Automation Vulnerability Policy.

Improved Product Resiliency for Firmware Revisions 33.016, 34.013, and 35.012

Product improvements have been made to increase product resiliency to potentially disruptive activities. These enhancements have been verified not to affect product safety, performance, expected life, configuration, or operation of the product. Rockwell Automation recommends that you follow good Industrial Control System (ICS) security practices that include regular product updates. To maintain authenticity, obtain product updates and new releases directly from Rockwell Automation.



  

Known Anomalies from Previous Releases

These anomalies are from previous releases but are still known in this release.

Mechanical Brake Delay (Lgx00113541, Lgx00107169)

Anomaly

Logix Firmware/RSLogix 5000™ Software 19.011

Catalog Numbers 1756-L61, 1756-L61S, 1756-L62, 1756-L62S, 1756-L63, 1756-L63S, 1756-L63XT, 1756-L64, 1756-L65, 1756-L72, 1756-L73, 1756-L74, 1756-L75

Logix Firmware/RSLogix 5000 Software 20.011

Catalog Numbers 1756-L71, 1756-L72S, 1756-L73S, 1756-L73XT, 1756-L73SXT

Catalog Numbers 1769-L18ERM-BB1B, 1769-L27ERM-QBFC1B, 1769-L30ERM, 1769-L33ERM, 1769-L36ERM

This anomaly occurs only in Integrated Motion on the EtherNet/IP network applications.

When you create a new CIP axis, the default value for Mechanical Brake Delay = 0. If you are using a motor with a brake on this axis and do not change the Mechanical Brake Delay value, the motor will not work properly when you attempt to execute motion.

To work around this anomaly, make sure that you set the Mechanical Brake Delay to the appropriate value before executing motion.

 

 

MSF Instruction (Lgx00113540, Lgx00108486)

Known Anomaly First Identified As Of

Catalog Numbers

- 1756-L61, 1756-L61S, 1756-L62, 1756-L62S, 1756-L63, 1756-L63S, 1756-L63XT, 1756-L64, 1756-L65, 1756-L72, 1756-L73, 1756-L74, 1756-L75 - Firmware Revision 19.011

- 1756-L71, 1756-L72S, 1756-L73S, 1756-L73XT, 1756-L73SXT - Firmware Revision 20.011

- 1769-L18ERM-BB1B, 1769-L27ERM-QBFC1B, 1769-L30ERM, 1769-L33ERM, 1769-L36ERM - Firmware Revision 20.011

This anomaly occurs only in Integrated Motion on the EtherNet/IP network applications.

Every time there is a Motion Servo Off (MSF) instruction/Motion Servo On (MSO) instruction cycle, the Position Trim value is added to the axis position. This change in axis position causes the axis to move unexpectedly by a distance equal to the Position Trim value.

 

Absolute Feedback Offset (Lgx00076298)

Known Anomaly First Identified as of:

Catalog Numbers:

 

If you issue an Absolute Feedback Offset, it results in a feedback fault. If you issue an Absolute Feedback Offset via an SSV instruction on the 1756-M02AS module, the result is a feedback fault. The feedback fault occurs regardless of whether feedback is on or off.

Logix CPU Security Tool

Known Anomaly First Identified as of Firmware Revision 20.011

RSLogix 5000™ Version 20.00

Studio 5000 Logix Designer™ First Identified as of Version 21.00

 

Catalog numbers:

Axis Schedule Changes After Project Import and Download (00169297)

Known Anomaly First Identified as of Firmware Revision 27.011

Catalog Numbers:


An axis schedule can change when you import a Studio 5000 Logix Designer® application, versions 24 and 26, project into Logix Designer application, version 27.


PI Function Block (Lgx00070832)

Known Anomaly First Identified as of:

 

The PI Function block appears to stop executing as the output does not change and instruction faults are logged.

If the PI instruction is being used in Linear mode, this floating-point equation is used to calculate the ITerm.

graphic

Due to the use of the single-precision floating point values, it may be possible, depending on the values of WLD and KP, for the ITerm value to be small enough, less than 0.0000001, to be lost when adding to the ITermn-1.

For more information regarding the PI instruction, see the Logix5000™ Controllers Advanced Process Control and Drives Instructions User Manual, publication 1756-RM006.

 

Real Time Axis Attribute of VelocityFeedback (Lgx00107793)

Known Anomaly First Identified As Of:

Catalog Numbers 1756-L61, 1756-L61S, 1756-L62, 1756-L62S, 1756-L63, 1756-L63S, 1756-L63XT, 1756-L64, 1756-L65 Version 18.011

Catalog Numbers 1756-L72, 1756-L73, 1756-L74, 1756-L75 Version 19.011

Catalog Numbers 1756-L71, 1756-L72S, 1756-L73S, 1756-L73XT, 1756-L73SXT Version 20.011

 

This anomaly occurs only in SERCOS applications that use Kinetix SERCOS drives and linear motors.

Under certain conditions, it is possible that the Real Time Axis attribute VelocityFeedback contains an incorrect value. The inaccuracy is the result of incorrect scaling of that attribute.

Your program will have an incorrect value for the VelocityFeedback attribute if you follow these steps.

  1. While offline, you write your RSLogix 5000 program and, as part of that program, the VelocityFeedback attribute is selected.
  2. You save the program and download it to the controller.
  3. You go online.

The VelocityFeedback attribute value is incorrect because that attribute was enabled before the program was saved, downloaded, and put online.

To work around this anomaly, do not enable the VelocityFeedback attribute until the RSLogix 5000 program is online.

 

Arithmetic State Flags (Lgx00122480)

Known Anomaly First Identified as of Firmware Revision 20.011

Catalog Numbers:

 

  1. When dealing with Floating point numbers, the controller does not truncate denormalized values or -0.0… 0.0.
  2. For an integer divide, when the denominator is 0, the S:N and S:Z are not set.
  3. For the MOD instruction, the S:V is not set if an overflow occurred during the calculation.

MAM Instruction With Merge Enabled (Lgx00078822)

Known Anomaly First Identified as of

Catalog numbers:


Under some rare occurrences, if a Motion Axis Move (MAM) instruction with Merge Enabled is activated during the deceleration segment of an active MAM instruction then the new MAM instruction may overshoot its programmed endpoint. The occurrence of the overshoot depends on the following factors:

•The original MAM instruction's remaining travel distance at the time of the merge and the new MAM instruction's remaining travel distance

•The relationship of the decel jerk of the new MAM instruction to the decel jerk of the original MAM instruction

•If the original MAM instruction is decelerating

 

Typically, the overshoot does not occur. If either of the following conditions exist, you will avoid the overshoot:

•The new MAM instruction is programmed with Merge Disabled. If there is no other motion active at the time of the merge, then the Merge Disable results in the same operation as the Merge Enable.

•The new MAM instruction has a slightly higher jerk (in units/seconds3) than the original MAM instruction. You should note, though, lower value of jerk in % of time results in higher value of jerk (in units/seconds3).

 

Excessive Velocity Error (Lgx00105360, Lgx00105595)

Known Anomaly First Identified as of:

Catalog Numbers:


IMPORTANT: This anomaly occurs only in applications that use Integrated Motion on the EtherNet/IP network.


With any coordinated move in a system that uses two or more CIP axes, if one axis is disabled using a Motion Servo Off (MSF) instruction, any remaining CIP axes will generate an Excessive Velocity Error, that is, Drive Error S55.

Accept Edits (Lgx00122528, Lgx00122622)

Known Anomaly First Identified as of Firmware Revision 20.011

Catalog Numbers:

 

When you accept edits in LD, ST, and FBD, the controller will log an 'Online Edit' entry in the controller log. Accepting edits in a SFC routine is done by performing a partial import, resulting in a 'Transaction Commit' entry in the controller log. This is confusing because you can select to mask both entries separately. Selecting only Online edits would cause the Audit Value to change only when FBD, ST, and LD edits are made. SFC online edits would change the Audit Value only if the 'Partial Import Online Transaction Completed' bit was set.


Corrected: Logix Firmware 20.014 for only

● 1756-L61, 1756-L62, 1756-L63, 1756-L63XT, 1756-L64, 1756-L65
● 1756-L71, 1756-L72, 1756-L73, 1756-L73XT, 1756-L74, 1756-L75


Absolute Immediate or Passive Home (Lgx00135080, Lgx00134716)

Anomaly

Logix Firmware/RSLogix 5000 Software 20.013, 21.011

Catalog Numbers:

● 1756-L61, 1756-L62, 1756-L63, 1756-L63XT, 1756-L64, 1756-L65

● 1756-L61S, 1756-L62S, 1756-L63S

● 1756-L71, 1756-L72, 1756-L73, 1756-L73XT, 1756-L74, 1756-L75

● 1756-L71S, 1756-L72S, 1756-L73S, 1756-L73SXT



Prior to RSLogix 5000 software, version 19.00.00, you could perform either an absolute immediate (SERCOS only) or a passive home with the drive in a safe off state. In RSLogix 5000 software, version 20.00.00, that feature was inadvertently changed to be blocked and generates the error 16#0028 'You are trying to run a motion command when the drive is locally disabled'.
 

Disable Download Project Documentation and Extended Properties Features (Lgx00135928)

Known Anomaly First Identified As Of Firmware Revision 21.011

Studio 5000 Logix Designer First Identified As Of Version 21.00


Catalog Numbers:
- 1756 ControlLogix L7
- 1756 GuardLogix L7
- 5370 CompactLogix L1
- 5370 CompactLogix L2
- 5370 CompactLogix L3


IMPORTANT: The following restrictions apply to enabling or disabling the Download Project Documentation and Extended Properties feature and should be considered collectively. Any, or none, of these restrictions might apply to your application.

Restriction #1
Storing your project comments and tag descriptions in the controller can increase upload/download times. Be aware of the following:
• If you click the Cancel dialog box during the Finalize portion of the download process, the download process continues to successful completion and you may not be able to access the controller for long as 10 minutes.
• If the Finalizing portion of the download process takes longer than 10 minutes, the controller can generate a Major Non-recoverable fault (MNRF).

To work around this restriction, clear the Download Project Documentation and Extended Properties checkbox when downloading the project.

Restriction #2

IMPORTANT: This restriction exists only in environments that use multi-workstation development.
If you are using multi-workstation development, we strongly recommend that you configure the Logix Designer project to include all project documentation and extended properties when downloading a project to the controller.
This configuration setting is the default setting.
A Logix Designer project can lose content from the text boxes for routines written in either Function Block Diagram (FBD) or Sequential Function Chart (SFC) programming languages when both of the following conditions exist:
• Multiple workstations are online with the controller.
• The project is configured such that the Download Project Documentation and Extended Properties checkbox is cleared.
When project edits are made at one workstation, the content in the text boxes of edited routines are deleted from all of the other workstations in the environment.
To work around this restriction, configure the Logix Designer project so that the Download Project Documentation and Extended Properties checkbox is checked.

IMPORTANT: Consider the following:
• This anomaly does not apply if your Logix Designer project uses Ladder Logic (LL) or Structured Text (ST) programming languages.
• A restriction applies to when you check the Download Project Documentation and Extended Properties checkbox.

Restriction #3

IMPORTANT: This restriction exists only in environments that use multi-workstation development.
If you are using multi-workstation development, we strongly recommend that you configure the Logix Designer project to include all project documentation and extended properties when downloading a project to the controller.
A Logix Designer project can temporarily lose content in the Rung Comments sections when all of the following conditions exist:
• Multiple workstations are online with the controller.
• The project is configured such that the Download Project Documentation and Extended Properties checkbox is cleared.
• The Logix Designer project uses the Ladder Logic programming language.
When project edits are made at one workstation, the content in the Rung Comments sections for the project rungs is briefly hidden in all of the other workstations in the environment.

When rung edits are finalized on the workstation that is making edits, the content in the Rung Comments sections for the project rungs reappears in the in all of the other workstations in the environment.

To work around this anomaly, configure the Logix Designer project so that the Download Project Documentation and Extended Properties checkbox is checked.
 
Controller Can Assert When Motion Instruction Accel And/Or Decel Operands Are Out of Range (3341103, 3453881, 3453882, 3453883, 3453889)
  
Controllers
First Known in Firmware Revision
Corrected in Firmware Revision
CompactLogix® 5370
20.011
37.011 and later
Compact GuardLogix® 5370
28.011
37.011 and later
ControlLogix® 5570
20.011
37.011 and later
GuardLogix 5570
20.011
37.011 and later
CompactLogix 5380
29.011
34.015, 35.014, 36.013, 37.011 and later
Compact GuardLogix 5380 SIL 2
31.011
34.015, 35.014, 36.013, 37.011 and later
Compact GuardLogix 5380 SIL 3
32.013
34.015, 35.014, 36.013, 37.011 and later
CompactLogix 5380 Process
33.011
34.015, 35.014, 36.013, 37.011 and later
CompactLogix 5480
32.011
34.015, 35.014, 36.013, 37.011 and later
ControlLogix 5580
28.011
34.015, 35.014, 36.013, 37.011 and later
GuardLogix 5580
31.011
34.015, 35.014, 36.013, 37.011 and later
ControlLogix 5580 Process
33.011
34.015, 35.014, 36.013, 37.011 and later

When MAM, MAJ, MCD, MAG, and MAS instruction Accel and/or Decel operands are near zero, a controller assert can occur.

For more information, see Knowledgebase Article Studio 5000® Motion Instruction Error Code 13 Accel and Decel out-of-range limits.


Alarm Log Content Lost at Powerup (Lgx00138163)

Known Anomaly First Identified as of Firmware Revision 24.011

Catalog Numbers:

 

Alarm Log content can be lost if there is a Secure Digital (SD) card in the controller that contains a project that is configured to load the project on powerup.

Controller Appears to Be Stuck in the Transition to Run Mode (Lgx00154875)

Known Anomaly First Identified as of Firmware Revision 24.011 for:

Corrected Anomaly as of Firmware Revision 1.013 for 1732E-OB8M8SR

Known Anomaly First Identified as of Firmware Revision 1.012 for 1732E-OB8M8SR 


If your project uses a 1732E-OB8M8SR module, upgrade the module firmware to firmware revision 1.013 or later.

Incorrect Execution Schedule for Scheduled Output Module (Lgx00157174)

Known Anomaly First Identified as of Firmware Revision 24.011

Catalog Numbers:


This anomaly occurs with only 1756-OB16IEFS and 1732-OB8M8SR Scheduled Output modules.


The Scheduled Output module may schedule outputs incorrectly if the Motion Arm Output Cam (MAOC) instruction is enabled before the module’ s connection is in the RUNNING state. The following sequence must occur to observe the anomalous behavior.

  1. The MAOC issues a new schedule before the Scheduled Output module connection enters the RUNNING state.
  2. A change in system time occurs between the time the new schedule is created and the connection entering the RUNNING state.

To work around this anomaly, update your logic to verify that the scheduled output module is in the RUNNING state before executing the MAOC instruction.

Controller can Assert When Stopping an Axis That Is Executing an S-Curve Profile Jog (4913301, 4976159)
  
Controllers
First Known in Firmware Revision
Corrected in Firmware Revision
CompactLogix™ 5370
20.011
38.011 and later
Compact GuardLogix® 5370
28.011
38.011 and later
ControlLogix® 5570
18.012
38.011 and later
GuardLogix 5570
20.011
38.011 and later
CompactLogix 5380
28.011
38.011 and later
Compact GuardLogix 5380 SIL 2
31.011
38.011 and later
Compact GuardLogix 5380 SIL 3
32.013
38.011 and later
CompactLogix 5380 Process
33.011
38.011 and later
CompactLogix 5480
32.011
38.011 and later
ControlLogix 5580
28.011
38.011 and later
GuardLogix 5580
31.011
38.011 and later
ControlLogix 5580 Process
33.011
38.011 and later

A controller assert can occur when a Motion Axis Stop (MAS) instruction is executed on the same axis that is concurrently executing an S-Curve Motion Axis Jog (MAJ) instruction.

Work arounds to consider:

• Change the MAJ profile from S-Curve to Trapezoidal.
or
• Add a condition to prevent MAS on an axis where MAJ with S-Curve profile is in progress; this would involve the axis .IP bit.

  

Attribute Values Incorrect with Set System Value Instruction (00169713)

Known Anomaly First Identified as of Firmware Revision 27.011

Catalog Numbers:

                                                    

When you use a Set System Variable (SSV) instruction to set the values for attributes available with the WallClockTime class, the values can be set incorrectly.



Wall Clock Value Different From Previous Value (00169756)

Known Anomaly First Identified as of Firmware Revision 27.011

Catalog Numbers:


After you set the wall clock for a controller, the actual time can be offset from the value that you set by approximately 2 seconds.

This anomaly occurs after Precision Time Protocol (PTP) is disabled in a controller that was previously synchronized with the grandmaster clock.



Expiration Times On a Logix Repository Record Can Differ (00171229)

Known Anomaly First Identified as of Firmware Revision 27.011

Catalog Numbers:


When the Logix Repository deletes a record, the cached value of the earliest expiration time and the actual expiration time value of the record can be different.



Unconnected Timeout Time Incorrect (00171872)

Known Anomaly First Identified as of Firmware Revision 27.011

Catalog Numbers:


The unconnected timeout time can be longer for a Forward Open service than expected.



Motion Run Axis Tuning Instruction Gets Stuck (00172234)

Known Anomaly First Identified as of Firmware Revision 27.011

Catalog Numbers:


A Motion Run Axis Tuning (MRAT) instruction can get stuck and the .IP (In Process) stays set to 1. This anomaly can occur when the MRAT instruction is used to command a motion module to run a tuning motion profile for an axis, the instruction



Media Space Calculation Incorrect with 3rd-party Secure Digital Cards (00175295)

Known Anomaly First Identified as of Firmware Revision 28.011

Catalog Numbers:


The media space calculation that is done to determine the available memory on a Secure Digital (SD) card can be incorrect with 3rd-party SD cards that are 4 GB or greater.

This anomaly does not occur when you use SD cards available from Rockwell Automation. That is, the 1784-SD1 and 1784-SD2 cards.

We recommend that you use the SD cards available from Rockwell Automation with your controller.

While other SD cards can be used with the controller, Rockwell Automation has not tested the use of those cards with the controller. If you use an SD card other than those cards that are available from Rockwell Automation, you can experience data corruption or loss.



Motion Instruction Interference Can Prevent Axis From Being Enabled (00175334)

Known Anomaly First Identified as of Firmware Revision 27.011

Catalog Numbers:


Intermittent execution of a Motion Group Shutdown Reset (MGSR) instruction and Motion Servo On (MSO) instructions can result in an error on the MSO instruction and failure to enable an axis.



PhaseManager™ and SequenceManager™ Show Different States of Phase in Program Mode (00183769)

Known Anomaly First Identified as of Firmware Revision 28.011

Catalog Numbers:

If the controller is switched to Program mode while a sequence and phase are running, the phase state changes to idle and displays idle, while the sequence continues to show running. On transition back to Run mode, the sequence displays inactive.


Controller Anomaly with Continuous Task, Indirect Addressing, and CONCAT or DTOS (1442602)

Controllers
First Known in Firmware Revision
Corrected in Firmware Revision
CompactLogix™ 5370
29.011
—
Compact GuardLogix® 5370
29.011
—
ControlLogix® 5570
29.011
—
GuardLogix 5570
29.011
—
ControlLogix 5570 redundant
30.051
—


Controller applications with a continuous task with CONCAT or DTOS instructions where indirect addressing exists may result in a controller major nonrecoverable fault/assert when additional task(s) exist. See Knowledgebase Technote 5570/5370 Controller Anomaly with Continuous Task, Indirect Addressing and CONCAT or DTOS.


  

SequenceManager Event Client 2.0 Can Experience Slow Performance When Using the Start Up Recovery Option (1769621)

Controllers
First Known in Firmware Revision
Corrected in Firmware Revision
CompactLogix™ 5370
28.011
36.011 and later
Compact GuardLogix® 5370
28.011
36.011 and later
ControlLogix® 5570
28.011
36.011 and later
GuardLogix 5570
28.011
36.011 and later


After downloading a new project, the SequenceManager™ Event Client that started with the Start Up Recovery option should stop attempting to recover events immediately. However, the Event Client can continue to attempt recovery until the maximum number of events has been reached.

Workaround: Start the SequenceManager Event Client with the Start Up Recovery option disabled.



SequenceManager Event Client 2.0 Cannot Reliably Recover Events on Startup of The Service (1766682)

Controllers
First Known in Firmware Revision
Corrected in Firmware Revision
CompactLogix™ 5370
28.011
36.011 and later
Compact GuardLogix® 5370
28.011
36.011 and later
ControlLogix® 5570
28.011
36.011 and later
GuardLogix 5570
28.011
36.011 and later


Starting the SequenceManager™ Event Client 2.0 service with the Start Up Recovery option enabled can result in missing data.


  
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