Modbus communication stopped

Troubleshooting
1

Hello,
I have an installation of around fifteen T3-BBs which worked correctly during a few weeks. But to date five of them no longer communicate with the Schneider meters. When I test with Modbus Poll the communication works with the meters. I reset, updated a T3-BB but it still doesn’t work. I also hope it’s not a hardware problem. I attach one of the program here.
BTW the register 91 is set to 91 so the Main is still set as Master. I also tried with the SUB interface but no result.

10 REM CE_AGBT_P6
20 VAR21 = 16.65.MB_REG_FLOAT_ABCD3059
30 WAIT 1
40 VAR22 = 16.65.MB_REG_FLOAT_ABCD2699 / 1000
50 WAIT 1
60 REM CE_TGBT_P6
70 VAR26 = 16.66.MB_REG_FLOAT_ABCD3059
80 WAIT 1
90 VAR27 = 16.66.MB_REG_FLOAT_ABCD2699 / 1000
100 WAIT 1
110 REM CE_AGTB_P5
120 VAR11 = 16.67.MB_REG_FLOAT_ABCD3059
130 WAIT 1
140 VAR12 = 16.67.MB_REG_FLOAT_ABCD2699 / 1000
150 WAIT 1
160 REM REM CE_TGBT_P5
170 VAR16 = 16.68.MB_REG_FLOAT_ABCD3059
180 WAIT 1
190 VAR17 = 16.68.MB_REG_FLOAT_ABCD2699 / 1000
200 WAIT 1
210 REM CE_AGTB_P4
220 VAR1 = 16.69.MB_REG_FLOAT_ABCD3059
230 WAIT 1
240 VAR2 = 16.69.MB_REG_FLOAT_ABCD2699 / 1000
250 WAIT 1
260 REM CE_TGBT_P4
270 VAR6 = 16.70.MB_REG_FLOAT_ABCD3059
280 WAIT 1
290 VAR7 = 16.70.MB_REG_FLOAT_ABCD2699 / 1000
300 WAIT 1
310 REM CE_ZTE_ZRGE
320 VAR31 = 16.63.MB_REG_FLOAT_ABCD3059
330 WAIT 1
340 VAR32 = 16.63.MB_REG_FLOAT_ABCD2699 / 1000
350 WAIT 1
Cfg_T3000_09072024.prog (65.6 KB)

2

BTW the register 91 is set to 1 I meant

3

You confirm you have done a firmware update and that it was working before. My first guess is that the Rs485 signal needs to be checked out using an Oscilloscop email.

Lijun will study this report and get back ASAP.

Thanks for the good troubleshooting.

Maurice

4

Yes I have done firmware update and it was working before.
What do you mean by oscilloscope email, I don’t understand?

5

Email: Typo, sorry. Just test the rs485 signals with a (differential) oscilloscope.

Maurice

6

I understand but not having this type of oscilloscope to date and given the sensitivity of the project I was hoping for a simpler and faster solution. Especially since at this rate I will soon lose all 15 T3-BBs.

7

A scope should be in the required tools category in this business. It can pay for itself very quickly. They are under $100 on Amazon.

Maurice