Regarding PM5560 Firmware Update (from Version 2.8.3 to Version 4.5.0)

[T.Okada]

Hello,

We performed an update of the PM5560 from version 2.8.3 to 4.5.0. Using the FW Upgrade Tool (ver. 4.0),

we updated three units simultaneously. In the upgrade tool, all three units appeared to update successfully,

displaying “Upgrade Completed. Double click here to open webpage.”

Afterwards, to be sure, we checked the firmware versions on the meters’ displays.

On one unit, the version still showed as ver. 2.8.3, while the other meters correctly showed ver. 4.5.0

(despite all three units being under identical conditions).

In that state, the unit still showing ver. 2.8.3 could not be accessed via the web interface over either HTTP or HTTPS. After trying various steps, we confirmed we could access that meter with ION Setup.

In ION Setup (with display set to PM5500 Ver.4.0.0), we changed the HTTPS setting from Disable to Enable. Although ION Setup displayed an error message, that action triggered the meter to reboot,

after which the version updated correctly. The same issue occurred on a total of three units, and all were restored by following the same procedure.

Do you have any insight into the cause of this issue?
Also, we discovered this workaround by chance—would you consider it a proper corrective action?

Regards,

Okada

[Mehran_Mehrnia]

Hi @T.Okada 

As documented in the release notes, when a PM5560 is upgraded to any firmware version higher than 2.8.3, HTTP support is replaced by HTTPS with TLS 1.2. Therefore, after upgrading to version 4.5.0, HTTPS is enabled by default.

It appears that the Firmware Upgrade Tool successfully transferred the firmware image to the meter’s internal memory, which is why it reported “Upgrade Completed.”, however, in certain cases some internal modules (such as the web server, HMI, or HTTPS services) may not fully reload into the new firmware image until the meter performs a complete restart.

In this situation, the restart was triggered when switching from HTTP to HTTPS. I am not certain why this occurred on these specific units.

Hi @rohith-s @akash_das Could you share your thoughts on this behavior?

Best Regards,

-Mehran

L3 Expert Advanced metering

[akash_das]

Hi @T.Okada Thanks for sharing the observation. We will check on this and update you.

[Mehran_Mehrnia]

Hi @akash_das,

Hi @rohith-s 

If you could share any updates or thoughts on this, it would be helpful to better understand the status, root cause, and any available workaround.

Best Regards,

-Mehran
L3 Expert Advanced metering

[rohith-s]

Hello @T.Okada & @Mehran_Mehrnia ,

We attempted to reproduce the reported scenario in our test environment but were unable to observe the same behavior.

As discussed earlier, during firmware upgrades, certain internal services (such as the web server, HMI, or HTTPS modules) may occasionally require a complete device restart to fully load and initialize the updated firmware image.

Based on the current observations, this appears to be isolated to one device still showing version 2.8.3 after upgrade, while the other two devices are operating as expected.

Could you please share the Firmware Upgrade Tool logs? Reviewing them will help us better analyze the upgrade sequence and identify any unexpected behavior during the process

Regards,

Rohith S

[akash_das · Accepted solution]

Hi @T.Okada 

FYI: We have not found such issues with our tested meters.

Root cause:
This behavior is most consistent with an incomplete firmware activation scenario, where the firmware image is successfully transferred but not fully applied due to a missed or ineffective reboot cycle. The observed workaround (triggering a reboot via configuration change) is effective as a recovery method.
This should be treated as a potential firmware or upgrade tool defect, and further information is needed on this. Please raise a BFO case to proceed further on this with below information.

Did we observe the HMI during the firmware upgrade process (e.g., any on screen information like flash erase, write, verification steps etc)?
After the upgrade tool reported success, did the affected device undergo a clear reboot cycle?
No of times restart of the device before and after upgrade same or incremented?
Did single meter upgrade has same issue?
share firmware upgrade tool logs.
Using webserver of the meter, share upgrade status (the last upgrade status) snap. For this go to: Maintenance->Upgrade->Upgrade status.