QJ71MB91

[Miften 1]

Good Day Again This time I come to you with question about Modbus control. Im using in my project 3 Modbus modules QJ71MB91. Everything works perfectly, but sometimes errors occurs of reply timeout from slave. I accept that this is normal. But I would need to have control over it! I must prepare an alarm if communication from slaves get disrupted (i.e. wire disconnected, slave turned of = many timeout errors). I worked a simple program which counts number of errors in 1 minute. If its high - it generates an alarm of Modbus Error. Problem occurs when there is only few alarms - I wanted to do "error clear Request" I prepared everything according to manual - but nothing happens, error from Module is not cleared (and it looks bad if Inspector sees on 3 modules Red Error Leds) also I tried to "Force' error led to turn off also I didnt turn it off. And my system have a flaw - if error counter reaches 65000 of errors - which will happen in system in long time - then I will not be able to monitor error - because the counter just stops. And if I understand the manual - only way to reset the counter is to reset the communication ? How to reset it? I cannot restart WHOLE PLC to reset counters of Modbus modules! It would be dumb. I hope this time also You will be able to help me. M.Z.

[Miften 1]

I do not know what happend to posts in this topic but they are lost. My question is that you mentioned you have FB to reet error led. Can you share this FB? Instructions in manual does not fit real GX Works data i.e. Error clear/ buffer memory addreses.

[ducna 1]

Hi everyone,

Does anyone have an answer to this problem?

Regards,