Unless the meter is secondhand or you have changed the id yourself, set the address = 47 in emonhub and leave it as that whilst you try other things like polarity. Unless you have reason to believe the address isn’t 47, we have no reason to not believe the manual and stick with that (for now!).
Do you have the sdm120 usb adapters connected? Have you deleted the modbus interfacer whilst testing the Mbus? Focus on one at a time and keep the other well out of the frame.
To “delete” the modbus interfacer (or any other interfacer), just add a hash (#) to the line that defines the interfacer Type eg
[[SDM120]]
#Type = EmonHubSDM120Interfacer
[[[init_settings]]]
device = /dev/ttyUSB0
baud = 2400
[[[runtimesettings]]]
pubchannels = ToEmonCMS,
read_interval = 10
nodename = SDM120
if any interfacer config is minus a Type it is ignored, it’s much easier than deleting or commenting out the whole section each time.
Can you execute this command
printf 'alias lsser="ls -la /dev/{tty{ACM,AMA,S,USB},serial}* 2>/dev/null"\n' >> ~/.bash_aliases && source ~/.bashrc
from here on in you can check the serial and usb device addresses with just a lsser command.
pi@RedPi:~ $ lsser
lrwxrwxrwx 1 root root 5 Jan 26 14:17 /dev/serial0 -> ttyS0
lrwxrwxrwx 1 root root 7 Jan 26 14:17 /dev/serial1 -> ttyAMA0
crw-rw---- 1 root dialout 204, 64 Jan 26 14:48 /dev/ttyAMA0
crw-rw---- 1 root dialout 4, 64 Jan 26 14:48 /dev/ttyS0
crw-rw---- 1 root dialout 188, 0 Feb 3 19:42 /dev/ttyUSB0
if you can check to see what devices we have, with just the Mbus connected do you have USB0? If not, start again by rebooting the Pi without the adapter, run lsser then plug in the usb mbus adapter and check again, USB0 should hopefully pop up on the 2nd run.
With the device /dev/ address confirmed and the id address = 47, try again, if no luck, reverse the 2 wires and try again.
I was in the process of posting a similar reply to you on the modbus thread, but now my pasta’s cooked I must disappear for a bit of food without finishing. If I don’t nod off immediately afterwards, I will try and get back.