BW August 2015

8/3-8/4

Using the data from the calibration tests, I calculated ratios of the temperature measured by the free thermistor to the temperature measured by the fixed thermistors. It was surprising that at certain times during the tests the ratios changed rapidly. The reason for the sudden changes was that the heating curves rise steeply from room temperature, and as the temperature rises their slope decreases. Where the slopes are steep, the ratio can change quickly when one curve rises faster than another. Another reason for sudden changes was the behavior of the heating curves once the temperature reached its target range.