Page 173 - Mechanical Engineers' Handbook (Volume 2)
P. 173
162 Temperature and Flow Transducers
Figure 22 Representative thermistor probes for temperature measurement. (Courtesy of Omega Engi-
neering, F4 of 1985 catalog.)
Resistance drift with time is a problem with some thermistor materials, especially at
higher temperatures. Park 41 recommends the addition of SiO to the mixture of oxides
2
generally used for negative-coefficient thermistor material as a means of stabilizing the
resistance–temperature characteristic.
The process is shown schematically in Fig. 23.
Figure 23 The thermistor manufacturing cycle.
