FAQs from Rohde & Schwarz

HMC8012 - Accuracy and range of Temperature Sensor measurements


I perform temparture measurements with the HMC8012 and a PT100 sensor. For the sake of completeness I want to add an uncertainty calculation to my results.
Unfortunately I could not find the PTxx00 measurement accuracy information in the datasheet. Please can you provide some additional information?


The uncertainty for the temperature measurement is based on the ohmic results.
There is no special mode, just calculating from the resistance:

HMC8012 - Accuracy and range of Temperature Sensor measurements

An example measurement with a 1051,9 Ohm resistor that gave a readout (for PT1000) of 13,3°C.
So the accuracy in my case - using the 4 kOhm range - is:

0,015 % of readout (1051,9 Ohm conforms to 13,3°C)
0,002 % of range (which is 4 kOhm)
(as 13°C is already outside the specified temp range of 18 - 28°C and we suppose the instrument to be in same temperature condition as the sensor is)
5 * 0,002 % of readout
5 * 0,0002 % of range

0,015 Ohm + 0,08 Ohm + 0,011 Ohm + 0,04 Ohm = 0,146 Ohm of uncertainty
which means that your measurand at the HMC8012 is somewhere between 1051,754 (13,3 °C) and 1052,046 Ohm (.13,3 °C).
This is better than the tolerance of the PT1000 class B which is +/- 1,428 Ohm or +/- 0,37°C.

We recommend to perform the measurement in 4 wire mode for best results.