Data logging through Modbus

Hi All

I am using Schneider Electric's Modicon Momemtum PLC (Concept software) with a Schneider Magelis HMI(Vijeo Designer software). The communication is Modbus between concept plc software and momentum plc. The application is to control 8 motors which performs specific tests.

The client wants logging of data for each tests from the PLC to an EXCEL CSV file. we suggested using Kepserver OPC server which will log Modbus addresses into CSV peridically but they are quiet expensive(£700) and is not an option.

Could you suggest any other method or software for logging. Thx.

Jai.

FasTrak SoftWorks makes a product called ControlShop, which has an OPC Driver with several demos included for VB, Excel, Active X... These demos would allow you to customize your code for your needs. Otherwise, the ControlShop product also has a stand-alone Logging/Trending component, which is OPC complient, and will Log data based on any criteria. See www.fast-soft.com.
Email me for further information: [email protected]

Modbus RTU protocol is public domain, so you could conceivably write your own PC program to read the data and save it to a CSV file. I think it would cost more in time than the driver (700 pounds = $1250).

An option may be AutomationDirect's DataLynx.

Seriously, when you look at the investment in time required to implement this, and compare it to the investment already made in PLCs and so on, the 700 pounds is probably a small percentage. Trying to do things on the cheap usually ends up more expensive! What is the total cost of one test?

Tom, if I were to write a program to read the data, could it read past integers/logged data? My problem is, if I get data logged, I need to have a one step process to take the data, put it in the format I need (simply changing the headers of the columns), and display it or print it. If I can get the GetData.EXE file from AB to do this, my problem would be solved, -or- if I could set "headers" or names before I pull the data, everything would work great. Im assuming I cant do either of those.

The customer wont have a COmputer hooked up during the "test" period, in which the logging occurs, thus the need to log it, then pull after the test.

Any thoughts?

Thanks
NH

Wow.. talk about ressurecting an old thread.

What PLC are you using nhicks?

Just about any PLC out there can use a timer and indexed addressing to store process data into what amounts to a table. From there, you need to extract the data into another application.

Even for "One-Time" applications, to me it's worthwhile to have a relatively powerful data-connectivity engine in your toolbox. One that is relatively inexpensive, and may even have a demo version that could work for a brief time, can be found HERE.

I really like to have the ability to pump information into (and out of) a database, or any other ODBC compliant application for that matter.

You could use just Excel, and a DDE/OPC server as well, but I really hate re-inventing the wheel over and over again.

Im using (hopefully) a Micrologix 1100.
Porblem is, I dont have a laptop hooked up during this test, and the control box is 12"x16", and mobile... the unit could be moved anytime, anywhere. If I can write a program that goes into the PLC, through the Ethernet port, to pull the data, then format it and save it to a .TXT or .CSV file, im good to go.. hard part is creating that program!

As long as you have an OPC or DDE version of Linx on the laptop, you can extract anything from an 1100 CPU. Or, actually, any AB CPU.

There are examples of sucking data into Excel in the RSLinx help file, and there are also lots of notes on the Rockwell Knowledgebase.

I suggested using a true OPC/DDE-ODBC/OLE data pump purely because it is like <fill in a brand> snack chips. You can't stop at <using it> one time.

Using simple OPC/DDE to get things into say Excel does require a great deal of manual labor and programming. Any of the commercially available data pumps, like the one I linked, are much much easier, and generally better. They can be set to trigger a transaction based on a change of a value, and pump the new value as well as a timestamp to a standard database format.

If this is just a performance test, why can't you plop an ethernet switch down, hook up the the PLC, HMI, and your laptop? Unless you are shipping a test unit somewhere, that they are going to collect some data for you to analyze later perhaps. If the latter, then just using Linx and Excel might be the best (albeit timeconsuming) way to go.

Hrm... if it's the latter, you can also just go online with the CPU, save the current program and data tables, export that save to ASCII, and manually parse them.

I forget, does the 1100 support the DLOG (DataLog) instruction? if so, you life may be easier.


For an unlimited budget, and AB systems, RSSQL is the ultimate, but it is (even for Rockwell) exceptionally overpriced.

rdrast, thanks for the help.
Here is a little more detail on the project.
We are manufacturing a load bank for a company.
They will (via forklift), move the loadbank to the test site, hook up to a generator... start the test. It will run for x hours, and take measurments every 5 minutes, of the following; Volts A, Volts B, Volts C, Amps A, Amps B, Amps C, Hz, KW. When the test is done, typically the generator cools off while the user will hookup the laptop and pull the data. There will be times that the generator stops prior the the data capture though. I need a setup where the customer simply connects, pulls the data, then has it displayed properly. We dont want the customer to have to pull the data, save it as an Excel sheet, then massage it etc.
The laptop comes in after the 2-3 hours test, wont be present/hooked up during the test. Dont necessarily have an unlimited budget, but getting the job done right, is always the key!

NH
Hope this clears it a bit.

NH