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Can’t change Thermocouple Type

Posted: Sat Jan 26, 2019 11:26 am
by adamgud
Hello there, I am using a Phidget 4 temp sensor 1048 and am having issues changing my thermocouple type within the control board. Its default is set to k-type but I have J-type thermocouples. When I change the thermocouple type from the drop down menu, it defaults back to K-type, resulting in an inaccurate temperature output.(several hundred degrees)
How do I change thermocouple types correctly?

Re: Can’t change Thermocouple Type

Posted: Mon Jan 28, 2019 12:00 pm
by mparadis
Are you saying that the thermocouple type changes back immediately after trying to change it, or do you mean it changes back the next time you close and re-open the Control Panel window?

If it's the latter case, this is normal behaviour since the 1048 has no on-board memory to remember which setting was selected. The Control Panel example for the 1048 defaults to K-type because it's the most common type. If you want to use J-type by default, you can write a program that sets the thermocouple type as soon as the program is started.

Re: Can’t change Thermocouple Type

Posted: Mon Dec 09, 2019 8:52 pm
by roasterx
Did you ever get this fixed as I have the same problem? Seems to only happen with phidgets library 22.

Re: Can’t change Thermocouple Type

Posted: Tue Dec 10, 2019 8:56 am
by mparadis
Yes, this occurs in Phidget22 because we wanted all properties of a device to be predictable when they are opened. In Phidget21, because properties persisted through attaches and detaches, it was difficult to know what state they were in if it was being accessed by multiple users or programs without meticulously checking each time.

The intended way to handle this issue is to set the thermocouple type in the TemperatureSensor object's attach handler. If you're using third-party software like Artisan, they should be handling this in their software in a similar way.

Re: Can’t change Thermocouple Type

Posted: Wed Dec 11, 2019 1:30 pm
by MAKOMO
Artisan is setting the TC type in the attach handler as intended. It uses the information the user configured in the Phdigets tab of the Device Assignment dialog.