To perform the calibration, connect the PRT to the data logger and program the data logger to
measure the PRT with the 4-wire half bridge as shown in the example section (multiplier = 1).
Place the PRT in an ice bath (@ 0 °C; R
s
=R
0
). Read the result of the bridge measurement. The
reading is R
s
/R
f
, which is equal to R
0
/R
f
since R
s
=R
0
. The correct value of the multiplier, R
f
/R
0
, is
the reciprocal of this reading. For example, if the initial reading is 0.9890, the correct multiplier is:
R
f
/R
0
= 1/0.9890 = 1.0111.
4WPB100, 4WPB1K PRT Bridge Terminal Input Modules
10
