METER THERMOMETERS

0˚C−100˚C Thermometer

00551828

Calibration

2. Remove short, adjust R2 for correct reading in centigrade

Lower Power Thermometer

00551829

†Select for operation at 1.3V

0˚F−50˚F Thermometer

00551830

Calibration

2. Remove short, adjust R2 for correct reading in ˚F

Micropower Thermocouple Cold Junction

Compensator

00551831

Adjustment Procedure

1. Adjust TC ADJ pot until voltage across R1 equals Kelvin temperature

multiplied by the thermocouple Seebeck coefficient.

2. Adjust zero ADJ pot until voltage across R2 equals the thermocouple

Seebeck coefficient multiplied by 273.2.

Thermocouple

Seebeck

R1 R2

Voltage

Voltage

Type

Coefficient (

Ω)(Ω) Across

R1

Across

R2

(µV/˚C)

(mV)

(mV)

J

52.3

5231.24k

15.60

14.32

T

42.8

432 1k

12.77

11.78

K

40.8

412953

Ω

12.17

11.17

S

6.4

63.4150

Ω

1.908

1.766

Typical supply current 50µA

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