Figure B.1 Thermistor Temperature Range - ILX Lightwave LDT-5500B Series User Manual

B
C H A P T E R
signal is available to the thermistor inputs of the LDT-5500B Series. The LDT-
5500B Series's measurement system will over-range when the input voltage
exceeds about 4.5 volts. Figure B.1 graphically shows the lower temperature and
upper voltage limits for a typical 10 K thermistor. (A 10 K thermistor has a
resistance of 10 k at 25
thermistor with the LDT-5500B Series are given in Table B.2, below. These
temperature ranges may vary from thermistor to thermistor, even though both
thermistors are nominally 10 K. This is due to manufacturing tolerances in the
thermistor, and is compensated for by determining C1, C2, and C3 (calibrating the
thermistor). The practical temperature ranges for a 10 K thermistor are also
shown as solid bars at the bottom of Figure B.1.
Table B.2 10K Thermistor Temperature Range
SENSING CURRENT
10 A
100 A
48
 LDT-5500B Series
Thermistor Range
TEMPERATURE RANGE
-30 to 30
10 to 70
5.00
4.50
4.00
3.00
THERMISTOR
VOLTAGE
2.00
1.00
0.00
-60
-40
* ILX default values for C1 and C2

Figure B.1 Thermistor Temperature Range

o
C). The practical temperature ranges for a typical 10 K
o
C
o
C
 o
(USING TYPICAL* 10 k @ 25 C THERMISTOR)
-20
0 20
DEGREES C
- Denotes practical range with typical 10K thermistor
- Denotes measurable range with typical 10K thermistor
60 80 100
40

10 A

100 A