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6-Contributor
October 3, 2016
Question

In signal processing haw to read in line analog instruments 4 to 20 mA

  • October 3, 2016
  • 3 replies
  • 1728 views

Mathlab has a way to read signal from analog instruments with 4-20 mA outputs

MAthcad has the same ability??

obiusly it need a card to transform the signal in real number  I need to read this real number into a vectorn

3 replies

23-Emerald IV
October 3, 2016

Note that there is a fundamental difference between Matlab and Mathcad:

Matlab is a programming environment (I see it as essentially a programming language) that you can use to model and execute a form of data processing, either on data files or on streaming data, with output to screen or file (or stream?).

Mathcad is an environment to enter, manipulate and execute mathematical constructs. You can perfectly use it to model a process and experiment with it, but Mathcad is more geared towards static applications, there are little to no features that support streaming of data.

If you have the data on file (either ASCII text or binary numbers) you can read the datafile into a Mathcad array or matrix and then process it. Then after processing you can store results in a file.

For reading in ASCII formatted data use READPRN, for binary data use READBIN. Writing data out is supported by WRITEPRN and WRITEBIN respectively.

Success!
Luc

12-Amethyst
October 3, 2016

Hola Gustavo.

In Mathcad 11 you have a Data Acquisition scriptable object. In quicksheets, check under "Using Mathcad with other applications". There are four examples for this DAC. In the help, you see that it is a National Instrument interface between the physical hardware from NI and Mathcad. Atached two images from this.

So, what you need is a hardware device to capture the data and an OCX or DLL device driver which can be inserted as OLE object in Mathcad, and write your oun vbscript or java script to pass the data into mathcad.

Attached some images of that.

Saludos cordiales.

Alvaro.

FIG.gif

FIG1.gif

FIG2.gif

21-Topaz II
October 3, 2016

I do not think you can do something in real time. You can import the records in Excel format.