On the C-more Micro connected to a DL-06, communication loss appears intermittently during PLC-commanded screen changes and seems tied to one screen. Treat that screen’s objects and tag configuration as the first diagnostic target; changing the navigation method does not correct a bad tag.
Stop repeating screen changes and changing navigation methods
When the fault clears or changes after another screen transition, repeating transitions may make the symptom look temporary without identifying its cause. The screen-specific pattern is more useful than whether the operator selects a screen with an F-key or the PLC requests it.
- Do not switch to F-keys as the repair. The reported transitions come from the PLC, but the suspected fault follows a particular screen. Changing who requests the screen does not repair an incorrectly configured tag on it.
- Do not treat intermittent behavior as proof of a flaky cable or PLC. A screen that contains an invalid tag can make the failure appear only when that screen is loaded or its objects are processed. Check the HMI error log before replacing hardware or changing the communications setup.
- Do not keep cycling screens without recording the result. Note which screen transition precedes the failure, then use the HMI’s error log to identify a specific configuration problem.
Use the affected screen to narrow the cause
A screen contains objects that read or write PLC tags. If an object references a tag that is not configured correctly, the HMI can report a tag error when that screen is involved. A consistent association with one screen therefore points first to that screen’s tag references—not to the PLC’s screen-change command by itself.
This is a diagnostic lead, not a reason to assume every communication interruption is a tag problem. The error log provides the deciding evidence: look for an entry identifying a tag that is not configured correctly. If it reports a different failure, follow that diagnostic rather than editing unrelated tags.
Read the C-more Micro error log
- When the problem occurs, open the HMI error log by pressing the upper-left corner of the screen.
- Find the error associated with the affected screen change. Record the tag named in the error and the screen where it appears.
- Compare that tag with the objects on the suspect screen and with the PLC tag or address it is intended to reference.
Use the log’s tag identification to focus the inspection. If no tag error appears, do not invent a tag correction: capture the exact logged message and investigate the corresponding communication or runtime diagnostic using the applicable C-more Micro and DL-06 documentation.
Correct the reported tag reference
In the HMI project, inspect the object or objects that use the tag named by the log. Check that the tag exists in the HMI configuration and that its PLC reference matches the intended DL-06 data location and the object’s intended use. Correct the project reference or tag configuration, then transfer the corrected project to the HMI using the established site procedure.
Do not change unrelated tags just because they are on the same screen. If the logged tag already matches the project and PLC configuration, verify the actual address and data type against the project and controller rather than guessing at a replacement. Keep a copy of the current project before editing so the prior configuration remains available for recovery.
Verify PLC-driven navigation after the correction
- Use the normal PLC-controlled screen-change sequence that previously exposed the issue.
- Repeat the transition to and from the suspect screen, observing whether HMI-to-PLC communication remains available.
- Reopen the error log and check whether the tag error has cleared. Confirm the screen’s displayed values or controls behave as intended.
Test the affected path more than once because the original symptom was intermittent. If the same log entry remains, the tag correction did not resolve the fault; recheck the named reference and its use on the screen. If communication still stops without a tag error, stop editing tags and move to diagnostics for the actual logged condition.
FAQ: C-more Micro and DL-06 screen changes
Can I use F-keys instead of PLC screen changes?
F-keys change how navigation is requested, not how the suspect screen’s tags are configured. Use the error log to investigate the screen-linked failure before treating a different navigation method as a repair.
Does a problem on one screen point to a bad tag?
It makes that screen’s tag references the first place to check. Press the upper-left corner of the display to open the error log and look for the tag it identifies.
Can I tell which tag is wrong without checking the log?
Do not guess from the screen contents. Read the error log and use its reported tag to focus the project inspection.
Does an intermittent fault rule out a tag configuration problem?
No. A fault that appears around transitions to one screen can still be tied to a tag used there. Correlate the transition with the error-log entry.
When should I stop troubleshooting and contact support?
Stop making project changes if the log identifies no misconfigured tag, the named tag matches the PLC reference, or communication still fails after correction. Save the exact error-log message, affected screen, and reproduction sequence, then contact official AutomationDirect support for C-more Micro and DL-06 guidance.