Shelly Pro3EM, Modbus query hangs after some hours (firmware ID: 20231219-134001/1.1.0-g34b5d4f)

mezzpezz

Hi,

I have been testing the modbus functions 31024, 31044, 31064 (read input registers for A, B, C active power values in W).

Everything works but if I keep pinging the Shelly Pro3EM over the same connection for some hours, apparently no matter how often (tested every 5 secs and 20 secs), the query hangs at least for 2 seconds.

After closing the TCP connection and opening a new one the query works again.

Is this a known software issue? Or is there a timeout on a modbus client even if the TCP connection is still active?

The error can be reproduced by running mbpoll from the command line every 5 seconds, eg:

Code

mbpoll -a 1 -t 3:float -r 1064 -0 -c 1 -l 10000 -v 192.168.1.23

Cheers