Themocouple USB-6353 3400 Celcius

[jolykj]

Hi Everybody

I have connected a thermocouple K-type to pin 55,56 on a NI USB-6353 board.

I have then tested with both MAX and LabVIEW: Thermocouple -SW-Timed Input.VI if the setup works.

The temperature input is what to be expected, except in both test set up, it display a temperature of 3400* Celsius often. This temperature is shown more if i physically touch the leading part of the thermocouple.

I have tried with different thermocouples, but have the same errors.

What could course the spike in temperature reading?

 

[Bob_Schor]

---

@jolykj wrote:

Hi Everybody

I have connected a thermocouple K-type to pin 55,56 on a NI USB-6353 board.

I have then tested with both MAX and LabVIEW: Thermocouple -SW-Timed Input.VI if the setup works. 

---

I don't have one of these boards, but the manual shows that pins 55 and 56 are AI Gnd and AO Gnd.  This seems "wrong", to me.

Bob Schor

[sukotgu2]

By the standards of industrial thermometry, this is an easy job. A low cost K type or N type TC or an RTD will do the job. In either case, it will need to be in a suitable sheath, i.e. corrosion resistant and low mass / thin wall to give fast enough response. Neither the corrosion, the temperature range nor the response time are difficult to achieve. I would expect to find an off-the-shelf solution.

[jolykj]

Hi Bob

It would have been nice if that was the mistake, so i appreciate the answer 😄

But sadly i use the USB-6353 and not the PCIe-6353, i assume you have looked on this:
https://www.ni.com/docs/en-US/bundle/pcie-usb-6353-specs/page/specs.html

[Bob_Schor]

Oops!  I didn't notice that the Spec sheet listed both the PCI and USB devices, and their pin-outs differed.  My apologies!

Bob Schor

[dr2]

jolyky,

Signals like that typically indicate an intermittent break in the TC circuit - such as a loose connection.

-Dave

[LVNinja]

Double check the terminal connections and the wiring. 

Try replacing the wires and ensure they are properly attached to the terminals.