An empty MR-J5 alarm history: why the current complete alarm still matters

Finding no entries when opening the alarm history during maintenance does not prove that the preceding abnormality did not occur. Current messages, alarm history and site observations are different sources that need to be checked against one another. Based on SH-030312ENG-P, this article concerns collecting MR-J5 fault information; it does not interpret an empty history as proof of a failed circuit board.

Understand the scope of the history

Section 1.1 explicitly lists items that are not entered in the history, including AL.010.1, AL.037, AL.11D and certain safety-parameter-related alarms. Warnings other than AL.0F0 are also not recorded in alarm history. The manual additionally uses detail numbers to distinguish messages within a group. Therefore, retain the complete current text and the detail number after the decimal point when checking the history; do not copy only the first few digits.

Create a record of the current condition on site

Photograph the current screen, amplifier display and nameplate, noting the time, equipment mode and action in progress. When recording detailed messages shown by software or a tool, also save the selected axis or station number so that another axis's data is not mistaken for the fault under investigation.

If the abnormality has already disappeared, record only the information actually retained. Do not reconstruct an alarm from similar photographs or label an operator's guessed number as confirmed. Distinguish “verbal description,” “site photograph” and “tool-exported record,” then add information when new evidence becomes available.

How to compare repeated events

1. Confirm that the amplifier and axis are the same before comparing complete alarms and detail numbers.
2. Arrange events chronologically, distinguishing the first occurrence from subsequent associated messages. Do not simply treat the last message as the initial cause.
3. Put actual changes such as power interruptions, part replacements and parameter adjustments on the timeline so repair personnel can assess connections.
4. Preserve original records before taking action. Do not clear the history just to tidy the display; if clearing is necessary, save it first and record the reason.

The next step once the information is available

Consult the troubleshooting table for the actual equipment model before arranging the necessary measurements or inspections. An empty history does not determine whether an alarm can be reset, which part of the machine must stop, or whether power must be cycled. If there is abnormal movement, a burning smell or repeated tripping, stop repeated trial runs and have the responsible personnel assess the equipment first.

For workshop repair or remote consultation, submit current messages, history screenshots and the event sequence together, indicating what was not recorded. When comparing with our FANUC 9137 case, only the method of retaining complete evidence is transferable. Alarm interpretations and component-replacement conclusions must not be applied across brands.

Reference: MR-J5 User's Manual (Troubleshooting), SH-030312ENG-P, §1.1, printed page 10; §1.2 List of alarm No./warning No. This article explains applicability and suggests how to organize site information. Perform specific work according to the documentation for the actual equipment and its machine builder.