The temperature accuracy and reference resistance tolerance offered by the PTS over a wide temperature range is exceptional. The equations shown here are used to develop the butterfly curves outlining the temperature accuracy at a given temperature point (tolerance class dependent) in Figures B and C respectively. As is evident in Figures B and C, the temperature accuracy is no worse than approximately ±2°C for a Class F0.6 PTS and approximately ±1°C for a Class F0.3 PTS between the wide operating temperature range of -55°C and 155°C. The accuracies are improved further with a customized Class F0.15 PTS. The resistance versus temperature table found in the PTS datasheet also includes temperature accuracies in 5°C increments.