64 34405A User’s and Service Guide
3 Measurement Tutorial
Temperature Measurements
The multimeter measures temperature by measuring the temperature
sensitive resistance of 5 k
W
thermistors.
Thermistors consist of semiconductor materials and provide roughly 10
times the sensitivity of an RTD. Because they are semiconductors, their
temperature range is more limited, commonly to –80
o
C to 150
o
C.
Thermistors have highly non–linear temperature–resistance relationships;
therefore their conversion algorithms are more complex. Agilent
multimeters use the standard Hart–Steinhart Approximation to provide
accurate conversions.
34405A users guide.book Page 64 Saturday, September 2, 2006 3:38 PM