Cannot skip to the next one when the 1st element of Modbus RTU encounters error

[myscada]

I’ve installed v5.8.4 and set up two elements (They belong to one RTU device, but have different data addresses) of a Modbus RTU device. If an error occurs when requesting the 1st element, the scada server cannot skip to request the next one after 3 retries. The server just requests the first element 3 times over and over again.

• This topic was modified 1 year, 3 months ago by myscada.

[manjey73]

I don’t know how it was done in the 6th version, but in the 5th it is, after unsuccessful attempts, all other groups were not requested. This is the default action.

[Mikhail]

You should find the cause of the error and fix the 1st request.
If the Modbus driver cannot get data, a communication session is interrupted.

[myscada]

Thanks for your replys. Actually these two elements represent two devices connected to a Modbus RTU device which transmits the private protocol of above two devices to Modbus. Sometimes the 1st element/device needs to be shut down for maintenance or repair which will cause the error of the 1st request.

[myscada]

If I use a PLC (e.g. Siemens S7-200 Smart) as a Modbus master to access the above Modbus RTU device (a protocol converter). The master can jump to the next element if the 1st request fails. I had thought that Rapidscada would handle it in the same way.

• This reply was modified 1 year, 3 months ago by myscada.

[Mikhail]

Actually these two elements represent two devices connected to a Modbus RTU device which transmits the private protocol of above two devices to Modbus

In this case, split the single Modbus device into several devices having different templates.
There is no option to continue a session if a request fails. May be we should implement it in the future.

• This reply was modified 1 year, 3 months ago by Mikhail.

[myscada]

Sorry for the late reply.

Thanks Mikhail, according to your solution it works now.

[Mikhail]

Thank you for the update 🙂

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