Hello Everyone,


2-wire Temperature Transmitter Details:

1.Model: TxisoBlock
2.Make: Novus
3.Accuracy: 0.3% of full span
4.Range: Configured for 0-600 deg C
5.Input: K type thermocouple
6.output: 4-20mA DC

I have used Multifunction Calibrator (PROVA 123) and RishMulti18s 5 and half digit Multimeter for Temperature transmitter testing.


I have applied a K type thermocouple input through
PROVA 123 And reading as follows<pre>
S.No Std Input/ Std Output/ Observed Output/ O/P Error/

1 /0 /4 /4.086 /0.54
2 /150 /8 /8.074 /0.46
3 /300 /12 /11.995 /-0.03
4 /450 /16 /15.947 /-0.33
5 /600 /20 /19.939 /-0.38</pre>
Except 12mA, All readings are out of Accuracy.

I thought Multifunction Calibrator also has some Accuracy. I have applied input like Actual Input in Below table <pre>
S.No/ Std Actual Input Std Observed O/P
Input Input Error Output Output Error
1/ 0/ -1/ -0.17/ 4/ 4.048/ 0.30/
2/ 150/ 149/ -0.17/ 8/ 8.024/ 0.15
3/ 300/ 300/ 0.00/ 12/ 12.01/ 0.06/
4/ 450/ 450/ 0.00/ 16/ 15.967/ 0.21/
5/ 600/ 601/ 0.17/ 20/ 9.974/ 0.16/ </pre>
Which table is Correct?
If table two is correct then Advice How Can i Justify it?

Kindly Advice

Thanks and Regards,
M.Kamaraj

 

so the Prova 123 has 0.1% of span, the transmitter you are testing 0.3% of span, so you can expect a 0.4% of span uncertainty in your test.

it seems that all is well

 

I don't think you'll find a type K thermocouple that's that good over that span anyways.

I didn't plot it, but it looks like a simple slope error. Tweak it and call it good.

Regards
cww

 

every tried a dry block calibrator on the tc

 

I presume the first simulation is Prova 123 K T/C output to temp transmitter.

It isn't clear what the 2nd simulation is. What is outputting to which input?

In the first simulation, has the Prova 123 calibrator been calibrated with traceable standards recently? You have the certificate? How much error did the K T/C range have when it was last calibrated?