Losing analog input calibration values?

Hi, I used Groov Manage via the browser to set an Offset and Scale for my pressure sensors (0-10V output sensors) connected to grv-ivi-12 (also have grv-itmi-8) analog input modules. Setting these in:
Module|Channel|Configure|Calibration values,
I was able offset the values so that the pressures on a group of sensors in the same air pressure line show the same pressure.

I then power-cycled the groov EPIC system, and found that I had lost all the calibration values - now show [0, 1], and all the displayed pressures are uncalibrated.

I then used PAC Control Basic, to set the I/O Units | Configure | Edit Analog Point |
[tick] send values and set the same offset / Gain into the dialog.
Save and upload to EPIC.

In this case the calibration values are kept, and survive a power restart of the EPIC.

I’m probably missing something… should the calibration values set with Groov Manage survive:

  • power reset ?
  • strategy upload ?
  • and how does the Groov Manage and PAC control Send Values part of the dialog work together (is it a one time thing, or is it stored in the strategy file, and the value is always sent ?)

p.s.: I’m adjusting the offset by trial and error, as I didn’t find a clear way to interpret the numbers: eg is the:
displayed value = Offset (V) + Scale * (raw voltage (V)) ?

I also notice groov Manage accepted, but then without notification when I looked at the Config page again - had lowered my offset without any warning. I now notice it says the offset is limited, depending on the voltage range set for the module, eg to "0.0625 V), which wasn’t enough to calibrate out the reading difference in one sensor. I think it was accepted in PAC Control though, again, I’m probably doing something silly ?


Sounds like you have hit one of these:


Can you take a moment and check your versions from module to EPIC.

I did firmware updates to current a few days before Christmas, but aren’t at the box with a laptop to copy out values at the moment: These are the downloads I used:
software: PAC Control Basic R 10.3d built 2020-12-18 12:01:41
groov EPIC: opto22.grv-epic-pr1.ignition8.3.3.2-b.93.x.field.bin, or
opto22.grv-epic-pr1.ignition7.3.3.2-b.93x.field.bin (I forget which).

I’m using degreesC only, and haven’t changed to degF mode at all, I don’t think the other results from the forum/knowledge base searches apply to my case…
I’d searched: calibrate, calibration, analog input, and the only thing that jumped out was the degF issue, which has been resolved since 3.3.0 anyway.

Reading your original post again with fresh eyes…
The strategy will always over write groov Manage. There is no way for the controller to know what values you have entered in groov Manage that don’t have data in PAC Control. (PAC Control will have zero as no data, there are no null areas in PAC Control).
If both places have data, which should the controller keep? So the strategy will always configure the I/O.
This is why your download is the final word.

As you have found, groov Mange is quicker to find the values you need, but you need to transfer them to the strategy and then download it at least once (with the save to flash and auto-run set as needed).

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