>>Message imported from previous forum - Category:SCADAPack RTU<<
User: mchartrand, originally posted: 2018-10-18 20:07:56 Id:136
This is a re-posting from the obsoleted (October 2018) "Schneider Electric Telemetry & SCADA" forum.
I am currently working on a water infrastructure project. In this project, Scadapack E535 RTU is used as a Modbus/Client and M580 PLC as Modbus/Server. Ethernet connection is established between RTU and PLC. I have configured the RTU using e-configurator( v 8.14.3) . Modbus scanner is used to read values from Modbus registers of PLC(M580).
While I am checking the values in point browser, I am not getting the right values from PLC(M580). The communication status displayed in Modbus scanner page of e-configurator is ‘device is online'. Yet, I am not getting the right values. I am sure that the mapping between points and Modbus registers are right in Modbus scanner. I have tried all sorts of combination- Word order(High/low),Byte order(High/Low) and bit order(High/Low).
I have attached the screenshots from e-configurator. While trying to write into the point browser, I am getting the following error-" Request: Page Write Request, Status: DNP Status: Control response received but the status indicated a problem". Thanks in Advance._**
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Why do you appear to have two configurations of Modbus scanner?
From your BRR_PLC version, you really could just have
Binary Input 10000
Point Quantity 48
No need to have the three entries.
None of the images you provided indicated in what way it wasn't working however.
I'd say that we have dozens, if not hundreds of sites deployed using the Modbus scanner, and whilst there are some known issues related to CROB functions not being supported, there haven't been many other issues..
Thanks for your reply. Yeah, I will change that(Points 10000-10047) to single entry in the modbus scanner.
The exact problem I am facing is that I am not able to read correct modbus registers from M580 PLC. For example, I was expecting values of 0.69 and 0.53 for modbus registers %MW40010 and %MW40012, which are mapped to points 10050 and 10051 respectively.
But, in the point browser, I am getting both these values as 0. There seems to be a gross mismatch between the registers I am trying to read from PLC and the registers I am getting from the PLC.
I have attached the project spec here along with the point browser values. Any pointers to solve this issue. Thanks in advance.
Also, I am not able to write any values via point browser to the PLC. While trying to write values via point browser, i am getting the following error" Control response received, but status indicated a problem"_**
Umm... %MW40010 is out of control...
I think perhaps you mean to use %MW0009, and then reference it from Modbus 40010.
%MW standard for 'address of Memory Word', not Modbus Word... so the two are not identically located.
The 4, 3, 0, 1 in the Modbus address actually relate to the memory access type (like an indication towards the function codes to be used) and aren't really part of the true address.
If you want to use %MW40010 then you will need to use 6 digit Modbus Addressing,
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Thanks a lot.
The 4, 3, 0, 1 in the Modbus address actually relate to the memory access type (like an indication towards the function codes to be used) and aren't really part of the true address. // This was the exact problem. I was using the %MW address from PLC as the Modbus reference.
Eventually, we used 6 digit modbus addressing to pull out %MW400XX address ranges._**
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Solved! Go to Solution.
I believe that modbus scanner function should be implemented in SCADA WORKBENCH software, configuring modbus scanner through e-configurator will not take effect, can any one confirm this???
I took the liberty to consult a member of our SCADAPack Tech Support team and he has indicated that:
"In SCADAPack Workbench for SCADAPack E, there are Modbus function blocks that can be used. Logic will be needed to drive the function blocks, however.
The Modbus Scanner in the E Configurator software is a way to configure Modbus polling without logic. Simple configuration can be used to get data without using code.
If you have further specific questions, you can contact "SupportTRSS@se.com"
If using an appropriate firmware and a SCADAPack E series RTU then the E-series Modbus Scanner functionality works very well.
It's been my preferred way to perform Modbus<->DNP3 mapping for years.
What specific issue do you have with this functionality?
The older way to achieve this was either via ISaGRAF IO Boards/Devices, and having Input Boards/Devices for one, and Output Boards/Devices for the other. But getting bi-directional signals was super annoying, with logic being required to map Modbus changes back into an OPERATE instruction on the input DNP3 point.