This forum uses cookies
This forum makes use of cookies to store your login information if you are registered, and your last visit if you are not. Cookies are small text documents stored on your computer; the cookies set by this forum can only be used on this website and pose no security risk. Cookies on this forum also track the specific topics you have read and when you last read them. Please confirm that you accept these cookies being set.

How to "Monitor Modbus" and find
#1
Hello,

I have on my installation 6 devices which are connected to LM4(this is the main task of this device) on 2 ports(1st and 2nd).

Both works with such parameters:
Baud rate: 9600,
Parity: None (1 stop bit)
Duplex: Half-duplex

1st port: 3 x Array PLC, 2 x PEGO Humidifier
2nd port: 1 x F&F LE-03MQ

1st port is used by Modbus mapper and I have on it 5 devices with 16 x coils, 10 x int32 and 88 x int16. Every device has minimum interval 10s. With 3 devices(addresses from 1-3) which every has few registers there is very, very rarely timeout error but normally they are working without any issue. But if it is next devices(humidifiers with addresses 4, 5) I see no errors in Error logs and when I use Read test there is absolutely no error, no timeout and responce is logical, same is on first read - every value updates GAs but further is is very, very unreliable. I've tried e.g. change GA value into other (from 8 -> 6) and with or without specified delta to 0.5 or 1 there is no update in 10s or 1 minute but maybe after a lot of minutes or hours or when I disable and enable Modbus mapper or I change some connection params like timeout or Poll interval which probably do the same.
1) What is the registers limit from the baudrate for such parameters? Am I near this limit or very, very far?
2) How can I monitor and find the reason of problem when there are no errors but objects aren't updated every Poll interval?

2nd is used for 1 energy meter and this is other subject and issue because modbus mapper has a lot of errors with this device(also when it is connected by a 0,5 cable, but I can read this device without any issue by ModbusPoll software with PC). But it is open question here:
https://forum.logicmachine.net/showthrea...ergy+meter
so I've created a separated script for reading a data with more tries for 1 register.

Can somebody help me solve this issue?

I think that it can be connected with this post:
https://forum.logicmachine.net/showthrea...bus+errors
Done is better than perfect
Reply


Forum Jump: