ITS-90 PRTscalibrated to ITS-90 R(.01),a, b, c, d, a4, and b4
IEC751 PRTs(RTDs) conforming to IEC-751 none
CVD PRTscharacterized by the Callendar-Van Dusen
equation
R0,Alpha, Delta, and Beta
YSI400 Thermistors matchingthe YSI-400 series none
THERM Thermistorscharacterized by the thermistor
polynomial
b0,b1, b2, and b3
Each of theconversion options is explained in the following sections along
with their associated coefficients,if they have any. The probe type and associ-
ated coefficientsare stored in the INFO-CON probe connector. Use the Up and
Downbuttons to select the probe type and the ENT button to store and
continue.
Each of the coefficientsthat follow the probe type, if there are any, are set in
theusualway.UsetheUpand Down buttons to set each digit and the ENT but-
ton to moveto the next digit to the right. Press ENT when all digits are entered.
7.8.9 ITS-90
The ITS-90 typeis for PRTs calibrated and characterized using the Interna-
tionalTemperature Scale of 1990 equations. This type of probe generally has
excellentaccuracy (0.005 to 0.025°C), a wide operating range (–180°C to
420°C or higher), butmay be rather expensive.The coefficients that appear
when ITS-90 is selected are “R(.01)”, “a”, “b”, “c”, “d”, “a4", and ”b4".These
should be setto the coefficient values that appear on the PRT calibration certifi-
cate according to thefollowing table.
Unused coefficientsmust be set to 0.
1521Coefficients CertificateValue
R(.01) Rtpw
a a5,a6, a7, a8, a9, a10, or a11
b b5,b6, b7, b8 or b9
cc6orc7
dd
a4 a4or a5
b4 b4or b5
Consider thefollowing examples.
Example1:
1521 Handheld Thermometer Readout
User’s Guide
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