Yesterday my IQ Gateway updated from firmware 8.3.5528 to 8.3.6005.
Immediately after the update, Modbus TCP stopped working again. My Cerbo GX can no longer communicate with the IQ Gateway, so the Enphase PV inverter is no longer available in VRM.
Has anyone else updated to 8.3.6005 and experienced the same Modbus TCP issue?
As an additional observation, after the same firmware update the official Enphase integration in Home Assistant also stopped working correctly. Most inverter telemetry is now reported as Unknown, although the system itself is operating normally.
Update: Enphase has enabled Modbus TCP for the third time, this time for version 8.3.6005, but the “Modbus exception 2: ‘illegal data address’” error persists. In my case, it still keeps sending three-phase data for a single-phase installation (I don’t know what improvements version 8.3.6005 brings, but it doesn’t fix any of my problems).
Wow I should have come directly to this forum.
I was wondering why my Enphase intergration stopped .. and AGAIN it is enphase if I read all these comments here.
Will start a support call with enphase AGAIN !
I hate their support and their system !
People do not buy Enphase !
Oooh the horror, I opened 2 cases but Enphase choose not to react to them so far.
Thus I called support. And now surprise surprise they have a new procedure for which they need the IP address of the Cerbo.
I am completely puzzled but hey whatever so I provided them the info, as all of my PV / ESS equipment has static IPv4 addresses and I have documented them. So far still no cigar. I also asked them why do you not update your documentation as you change your processes.
Why I am not able to do the configuration myself (like I am able on all the other major PV brands). But no answers, just sorry sir for your inconvenience.
And one should think support should be able to fix this within a few minutes, but call has been allmost 4 hours ago, still no change.
The system worked fine for over a year .. so why change a working product .. Enphase never seems to stop to annoy me
Requiring the Cerbo’s IP address is part of their procedure to restrict interaction with the gateway’s Modbus server to a single client. This is a security measure; otherwise, the Modbus interface would be completely exposed to any device on the local network. While owners of small private networks (mainly residential) generally don’t worry about this, those with larger private networks need to ensure their equipment is secure. As fobrs noted on my GitHub page, the next step is Secure Modbus, where communications between client and server will be encrypted and mutually authenticated. This is a goal set by the SunSpec Alliance that Enphase—along with many others—intends to meet to maintain compliance. In a world where the threat of cyberattacks is growing daily, it is good to see manufacturers moving in the right direction and ensuring security updates for their products.
Having said that, I went through weeks of hell dealing with support, which was simply not up to the task. Like you, I find the way this major change was handled—causing unannounced service interruptions—to be appalling.
My theory is that this rushed change was prompted by a potential security vulnerability in their old Modbus server. Unfortunately, Enphase is notorious for its lack of communication.
On August 6, with system version 8.3.5528, I encountered a similar problem. The Modbus service was returning error 6, “Slave Device Busy.” After a restart, the service became operational again.
The Envoy has been updated to SW VERSION D8.3.6022.260813, and I have lost Modbus-TCP access once again (this is the third time it has happened).
Furthermore, since Enphase replied:
“After reviewing the matter internally, I would like to clarify our support position regarding Modbus TCP on the IQ Gateway.
While SunSpec Modbus TCP is supported for monitoring and telemetry purposes, Enphase does not provide a supported interface for external control of PV production through Modbus write operations from third-party EMS platforms, including Victron Cerbo GX, Node-RED, or other external controllers.Therefore, although Model 704 registers may be visible through the SunSpec model map, Enphase cannot support, validate, or guarantee external active-power control, export management, curtailment logic, or dynamic production limiting through Modbus write commands.”
I have decided not to insist on this matter any further and will use Node-RED to retrieve the microinverter data instead.
My Enphase system was automatically updated to version 8.3.6022 two days ago. After that, I’ve lost Modbus connectivity and had to ask Enphase support (twice) to have it restored (I also had to specify the local IP of my Cerbo GX, which wasn’t necessary before).
As many have pointed out, the Enphase system now shows as a tri-phase inverter, with L2 and L3 around 0W.
Following the 8.3.6022 update, the Modbus TCP service has become unreachable once again. I have contacted Enphase. The service was restored within 24 hours. I have not received any feedback from Enphase regarding this matter.
I changed the unit id to 1. I read it somewhere. It could have solved this issue.
