I have built the log function into the PLC and we have analogue data now as a logged file.

the issue is that the data is now not being displayed as degrees c but as the number from the device.

is there a calculation I can use that can change the raw data to degrees c?

or can I use a maths function to change it for me?

thanks

Sorry I don't understand that,..i have used excel and can take the number divide by 10 and mius 15 that seems to be some what right but I don't know if I will keep the figure linear

PB

Sorry I don't understand that what you mean. You wrote in first post nothing from  excel.

Can you upload an example?

from the plc log file I can extract 2 numbers I am monitoring two analogues

the figures I get are they are measuring different points

AI1 297 AI2 293

297 / 10 = 29.7 this however is not the right figure if I take away 15 this = 14.7 this is the correct value in degrees C but is this the correct method? is it linear will it stay linear?

thanks by the way for the feedback

In attachment an example by AI from PT100/1000.

t your documentation it looks good. I would agree with what you have offered. my issue is that the analogue does not fall into the PT100 / 1000 very well. to get an accurate signal I have had to change / modify the standard settings -500 2000 to one that works for us.

There was a large error in the value when using the pre fixed value.

This I overcame by moving the values to what I needed so the pt100 would work.

I did try and find out if other people had the same problem..

The lead is very short and the sensor is from RS as a Pt100.

I don't have my PC with me today I will copy the program I place it on the system for you to review.

thanks again for your assistance

PB