3.72 Venus os does not reconnect to Modbus PV Inverter

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1

I use modbus for reading pv inverters via modbus sunspec protocol. When the modbus connection is disconnected venus seems not to reconnect (I waited for 30 minutes).

Some inverters go offline at night when no pv power is available. Also when the inverter is powered off for maintenance the connection fails.

Automatic scanning is enabled, although I use a fixed ip address.

Only restarting venus os solves the problem.

Tested with 3.72 and 3.80~14

2

Reopened. Apologies, weird caching issue with the site that made the topic exist in two places at once.
Relocated from beta as it is not a beta specific issue. Thanks.

5

Thank you!

6

Silly question. Did you manually add the fixed IP inverters or are you relying on scanning for them to appear? Wasn’t quite clear.
Which inverters and model are these? (been tons of issues with SolarEdge)

7

I did manually add the inverters, data is coming from nodered modbus server, which works fine until disconnect. I can connect to the modbus server without any problems any time. So I think this issue occurs with any pv inverter via modbus tcp (or udp?).

Screenshot20260506150208VRM
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Screenshot20260506150147VRM
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8

I also noticed a loss of the connection twice this month.

From 1 may 23:00 until I reconnected at 2 may 18:59 and from 5 may 2:07 until I reconnected 17:14.
Maybe Enphase did some software updates?

I didn’t manual add the IP and automatic scanning is on.

Strange enough I also see mine PV system 2 times and can’t delete the one without name.

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9

Maybe the reconnect functionality is not implemented or not working?

10

@nickdb you changed this topic to nodered, but it has nothing to do with nodered as @ron_h mentioned the same behavior with enphase.

It is the modbus tcp pv reconnect functionality in Venus os that is failing not nodered.

11

Wasn’t sure where it belonged exactly but after a chat to Dirk it belongs in mods so will move it. Have pinged the engineer who looks after sunspec as well. Just trying to get the right attention for you. Apologies for the chaos.

12

No problem, just trying to get a clear report pointing towards the right direction. Thank you

13

Just disconnected mine PV from AC and wait until it showed not connected.
The system does come back if power is restored, but in a strange way see picture.

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Maybe this startup is Enphase specific?

14

Forcing a short connection loss between cerbo GX and Enphase gateway also doesn’t reproduce the issue.

15

I don’t get the message not connected, the watt displayed just freezes and never refreshes again. How long did you have to wait for the not connected message?

What happens if you restart the pv inverter without waiting for the not connected message?

16

Just disconnected communication for 5 seconds, nothing happens.
Seems 2 different issues.
I don’t see a freeze, got a not connected and in VRM the PV is gone.
But maybe Enphase did update the firmware yesterday and this caused the communication loss,…

17

Is there any update to the various issues mentioned in this topic ? I’m on 3.80-21 beta but I have the same issues as you are describing. I cannot remove my decommissioned gateway from PV inverter section. I have the same nameless entry listed for the active envoy which I cannot remove. Rebooting is a hassle because restoring service is not guaranteed and my dynamic power limiting max power stays 0 no matter what I do.

Something new maybe the fact that it does not only show ac-in1 but also ac-in2. Technically, a MP2 is grid connected on ac-in2 and ac-in1 is not used. But if you change the Envoy to ac-in2 it removes from VRM :slight_smile: