RTD conversion enabled. What's going on here?

drbitboy said:

Hexadecimal constant i.e. H2222 = 8738 base 10?

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Mas01 said:

Thanks, I had no idea it was hex!
I've learnt something today!

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• Enter a constant value headed by K, H, E or '''' to ensure that it can beidentified as a decimal, hexadecimal, actual number or character stringconstant.

drbitboy said:

Maybe, I am only guessing; often the H is at the end for hex radix; a letter at the front usually says summat else about the number (where in memory, etc).


parky will know for sure, but see page 6-40 here.


Ah, found this in that manual, p. 5-10:

• Enter a constant value headed by K, H, E or '''' to ensure that it can beidentified as a decimal, hexadecimal, actual number or character stringconstant.

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parky said:

Correct the H denotes Hex K denotes integer E denotes float.
You can write to those with integer as well but in this case it is writing to buffer memory of an intelligent card and often the buffer memory word can be split into bytes nibbles or bits in this case it is to set the card to a particular mode.
Cannot remember exactly the buffer memory addresses but it is probably setting either 4 or 8 of the channels to a particular mode like PT100 sensor type in many cases each channel is assigned to a nibble (4 bits) for example 0/1/2/3
so writing to one word H3333 will set the 4 channels to that mode.
There are many buffer memory areas assigned to intelligent cards probably 255 although some are write only or read only and some cannot be written or read from as they are used internally.
Nowadays it is rare to set up intelligent cards this way as there are add on utilities to configure the cards like GXConfigurator-AD for analogue to digital cards.

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parky said:

Here is the manual, there is a lot to take in if you want to understand how it works, look at section 3 it gives the list & explanations of the buffer memories, there are many parameters that could be used like type of PT100, ranges, filters, offset & span settings the list is endless, on your other post regarding the subtraction of a value as an offset this could have been done within the program for calibration purposes but it's a lot of work so most people do not bother just add or subtract a bit around the expected range. Using the configurator is far easier.
I have just had a quick look at those addresses 164 & 165 and these seem to be offset settings but again chinenglish manuals do not make it very clear so are not the mode as such, I have only used the FX PT modules on all Q series I used 4-20ma and head converters in the PT100 probes, this gave us a quick way to calibrate them without touching the PLC code or pages of settings on HMI's.
https://dl.mitsubishielectric.com/dl/fa/document/manual/plc/sh080142/sh080142o.pdf

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