Fluke 7102 - Calibration Procedure; Compute DELTA

Micro-Bath
Calibration Procedure
35
Calibration Procedure
Follow these steps for the calibration procedure:
1. Choose three set-points to use in the calibration of the R0, ALPHA, and DELTA parameters. These
set-points are generally 2.5 °C, 45 °C, and 100.0 °C (36.5 °F, 113 °F, and 212 °F) but other set-
points can be used.
2. Set the bath to the low set-point. When the bath reaches the set-point and the display is stable, wait
about 15 minutes and then take a reading from the thermometer. Sample the set-point resistance
by holding down SET and pushing DOWN. Write these values down as T
1
and R
1
respectively.
3. Repeat step 2 for the other two set-points and record them as T
2
, R
2
, T
3
, and R
3
respectively.
4. Use the recorded data to calculate new values for R0, ALPHA, and DELTA parameters with the
equations given below.
Compute DELTA
A = T
3
− T
2
B = T
2
− T
1
E = R
3
− R
2
F = R
2
− R
1
T
1 − 3
– Measured temperature using thermometer.
R
1 − 3
– Value of R from display of product (push SET and DOWN simultaneously.)
where
T
1
and R
1
are the measured temperature and resistance at 2.5 °C
T
2
and R
2
are the measured temperature and resistance at 45.0 °C
T
3
and R
3
are the measured temperature and resistance at 100.0 °C






−






−






−






=
100
1
100100
1
100
22
33
TT
TT
C






−






−






−






=
100
1
100100
1
100
1122
TTTT
D
CFDE
BEAF
delta
−
−
=