Reading smartmeter Logarex LK13BE803039 via RS485 interface

[SuGe3]

Hi everyone,

need help to read Logarex via RS485 and Tasmota SmartMeter scripting.

reading the Logarex LK13BE803039 with a bitShake SmartMeterReader-UART (IR) and script:

>D
>B
=>sensor53 r
>M 1
+1,5,o,0,9600,LOGAREX,4,16,2F3F210D0A,063035310D0A 
1,1-0:1.8.0*255(@1,Total consumption, kWh,4
1,1-0:1.8.1*255(@1,REF T1,KWh,total_in,4
...

worked perfectly for 1.5 years, but gradually, incorrect data was transmitted more and more frequently, and then no data was transmitted at all. Obviously, the IR diodes of the Logarex are broken.

Since the network operator refused to replace the smart meter, I now want to read the smart meter via the RS485 interface. But I'm having trouble creating the script, Hardware seems to be working fine.

Hardware:
AZ-Delivery ESP32-WROOM-32 flashed with Tasmota32 (vers. 14.6.0) and user_config_override.h:

#ifndef USE_SCRIPT
#define USE_SCRIPT
#endif
#ifndef USE_SML_M
#define USE_SML_M
#endif
#ifdef USE_RULES
#undef USE_RULES
#endif
// Definition for MODBUS_INTEGRATION
#ifndef USE_MODBUS_BRIDGE
#define USE_MODBUS_BRIDGE
#define USE_MODBUS_BRIDGE_TCP
#endif

RS485 to TTL converter, like the one from the Tasmota Modbus Bridge documentation

Logarex type LK13BE803039 with RS485 cable installed by an electronics technician.

Wiring:
ESP32--->RS485 / RS485 ---> Logarex
TXD ---> TXD / A ---> RS485A
RXD ---> RXD / B ---> RS485B
5.5v ---> VCC
GND ---> GND

So far, so good, but... I'm struggling to create the correct script.

I've tried many combination but haven't received any correct decoded values yet.

1.) First, I tried using the same script with adjusted GPIOs as before:
+1,3,o,0,9600,LOGAREX,1,300,2F3F210D0A,063035310D0A
Result:
The TXD LED flashes, but the RXD remains off, no response from the Logarex.
Afterwards, I tried to send the request in F section with sml() command, logic similar as described for Landis + Gyr ZMR120AReS2R2sfCS (OBIS), but without baud-switch and use in M section just +1,3,o,0,9600,LOGAREX or +1,3,o,1,9600,LOGAREX, or +1,3,o,0,9600,LOGAREX,1, or +1,3,o,1,9600,LOGAREX,1
in any try got the same Result as before. Only TXD LED flashes, no incoming message.

2.) I tried SML instead of OBIS:
+1,3,s,0,9600,LOGAREX,1,300,2F3F210D0A,063035310D0A
Logarex responds, i.e., the TXD and RXD flash alternately. But in the console, using debug mode, I got nothing else as “Checking connection”

3.) I tried MODBUS:
+1,3,m,0,9600,LOGAREX,1,300,2F3F210D0A,063035310D0A
Logarex responds, i.e., the TXD and RXD flash alternately. In the console, with sensor53 d1, I got beside the timestamps the hex values for sending and receiving. I translated the HEX values to ASCII strings via an online tool, and got the following values, only these two respond lines nothing else:
(sent)>/?!
ߥ/LOG5LK13BE803039
(sent)> 051
+, P0 (6027) c

4.) Attempt to send "063035300D0A" (050) instead of "063035310D0A" (051):
+1,3,m,0,9600,LOGAREX,1,300,2F3F210D0A,063035300D0A
Logarex responds, both LEDs flashes, result in the console: Logarex sends all values as HEX-formatted strings, means if I convert the HEX values via the online tool, I got strings like:

1-0:2.8.0*255(000066.8791*kWh)
1-0:16.7.0*255(000374*W)
1-0:32.7.0*255(236.4*V)

The values within the brackets match those on the LOGAREX display.

5.) Best result I got with RAW request:
+1,3,r,0,9600,LOGAREX,1,300,2F3F210D0A,063035300D0A
Logarex even responds, both LEDs flashes, result in the console is identical to MODBUS, but the send strings are not displayed.
Here the console output and its conversion via online tool HEX to ASCII (same result as for MODBUS)

I have now tried x combination to decode the values using the Tasmota script, I tried MODBUS as well as RAW, but without success. Every try gives me other values, but never the correct ones.
For example:
Tried to get the Watt value 374 of String 1-0:16.7.0*255(000374*W),
which should also be a negative value -64 like 1-0:16.7.0*255(-000064*W):

1,pm(r312d303a31362e372e302a323535)xxuuuuuuuuuuuuxxxxxx@1,current,W,current,0
1,pm(h312d303a31362e372e302a323535)xxuuuuuuuuuuuuxxxxxx@1,current,W,current,0
1,312d303a31362e372e302a323535xxuuuuuuuuuuuuxxxxxx@1,current,W,current,0
1,312d303a31362e372e302a323535xxssssssssssssxxxxxx@1,current,W,current,0
1,312d303a31362e372e302a323535@#,current,W,current,0
1,312d303a31362e372e302a32353528@1,current,W,current,0
1,1-0:16.7.0*255(@1,Verbrauch aktuell,W,LG_current,0 <= output just 0, does not work at all
…

And hundreds other combination with UUuu, uuUU, ssSS, ... but got never the current values within the brackets.
Furthermore, I tried some special commands but also without success.

Maybe I'm wrong, but it seems that the Logarex send an OBIS code, but only respond if he received a MODBUS or RAW request. And it seems that the MODBUS and RAW decoder can't handle the OBIS-ASCII string.

I'm going crazy, the hardware and the serial request works as expected and the Logarex sends everything I expect, too. But I can't transfer the values to MQTT in the decoded, usual JSON format.

Is there a switch or command to say, just take the string? Or better a part of a string? I don't found a suitable command. Maybe a special command converting incoming serial messages to ASCII-string before sending to the decoder? Or something to change the format that needs to be used to decode the incoming message? Means send m or r and decode o.

Does anybody have an idea how do I get the received HEX-ASCII-string decoded?
Or is there a way to send the compete RAW-HEX to MQTT? Then I can code a converter myself, outside of Tasmota.

I also tried a Berry script but that’s another story, with other problems and even without success. :(

I would be very grateful for support or an idea how to...
Thanks in advance

[gemu2015]

this is a very unusual meter format.
decoding hex asci is not directly supported.
currently i assume there is no way to decode this even with raw mode.
please post a raw dump of your meter and i will check how it can be decoded probably by adding a new decode option.

probably other option
try to check with a smartphone camera if your meters infrared diode is still sending data.
then enlarge the pull-up resistor of the photodiode until it works again.
i could not find a schematic of the bit shake reader, so you have to identify where the pull-up resistor is.

[gemu2015]

in this version sending in obis without parity is enabled by another bit.
try with
1,=so2,20 instead of 10
this disables the hexasci to asci conversion and enables obis sending without parity (which is needed in your case)

xsns_53_sml.ino.zip

[SuGe3]

Regarding dump mode within the console:
if I use +1,3,r,0,9600,LO... I get hexasci obis,
if I use +1,3,o,0,9600,LO... the pure obis code is shown.

ok, I'll try again, it'll take a moment

[SuGe3]

Cool, it works!
I was hoping for help, but I didn't expect to get a solution so quickly.
You're my hero, thank you very much, great work!

[gemu2015]

ok, will do a pr soon
btw you may omit line now, no longer needed
1,=so3,80,1024

[SuGe3]

yes, default setting is working fine, good hint, thanks.