s7-1500 and tank level meter modbus RTU

[bentec]

I use an S7-1500, an MTP1200 Comfort Unified, and a WinCC V8 station. The S7-1500 communicates with a tank level meter via Modbus RTU (RS-485).

At the operator's request, I must read a tank profile composed of 250 points, each point containing the position, temperature, and density.

What is the recommended method for:

- storing these 100 samples;

- displaying the three curves (Position, Temperature, and Density) on the MTP1000 Unified and WinCC V8;

- recalling and displaying an recorded profile?

Thank you for your help.

[ISMNOP]

Hi

for your situation, if I was to only use a S1500 PLC, I would do something like this

1) create a UDT with 3 variables, one for each measurement in the proper data type + a time variable

2) create an array of 100 of the said UDT

3) each new point, I would shift the array by one and store the new point in the highest one

If you don't have time, you could get the LGF library on Siemens, it's free and got a register shift bloc.

Now, for the display, if you use a Siemens HMI there is already an object in TIA portal to make curves.

And for recalling and displaying a specific point, you could have a page where you would have 4 numerical outputs to display each measure and when it was acquired, two button to shift between adjacent points and a text box where you could write the index of the point you want to read.

But that's just from the top of my head. There might be better ways to do so.