We have a few CR5310-600 voltage transducers that are rated at 200ppm/C but we measured much higher thermal drift (we used calibrated oven, calibrated Fluke 8842A DMM, and calibrated powersupply).

Here are a data points from our measurements (also attached as JPG file):
Vin=608.41V Vout=5.0256V [54.1C]
Vin=608.40V Vout=4.9974V [44.0C]
Vin=607.14V Vout=4.7806V [33.5C]
Vin=607.74V Vout=4.5974V [23.9C]

Clearly you can see a significant thermal effect on the transducer output.

The power supply powering the transducer was not subjected to high temperature, only transducer itself.
Additional info on the transducer-
QC:1110; No. 09120032357; Lot# 102047

Can you please comment on this? We use several of these instruments in the field and are concerned about some of the readings we've seen recently.

Do you have an option for tigher tolerance or other higher grade instrumentation?

Sincerely,
AV