Thermo Scientific Sarasota FD910, User Manual

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Commissioning
Functional Checks
3-2 Sarasota FD910, FD950, & FD960 User Guide Thermo Fisher Scientific
If required, you can check the PRT separately by disconnecting terminals
W, X, Y, and Z and measuring the resistance across terminals X and Y. For
best results, make an allowance for the internal leads by using a 4-wire
method for reading resistance or by measuring and allowing for the internal
lead resistances.
To manually allow for the internal lead resistances, take the measurements
below, and then perform the calculation that follows.
●
Resistance across W and Y (Meas1)
●
Resistance across Z and X (Meas2)
●
Resistance across X and Y (Meas3)
Refer to Table 3–1 for resistance and corresponding temperatures. By
simultaneously measuring the line temperature using a separate PRT as
reference, you can determine the accuracy of the instrument PRT. While
performing this check, it is essential to allow the instrument to stabilize to
the line temperature and avoid rapid temperature fluctuations.
Table 3–1.
Temperature (
°
C) Resistance (ohms
Ω
) Tolerance
±
Ω
±
°
C
-20 92.16 0.05 0.13
0 100.00 0.04 0.10
20 107.79 0.05 0.13
40 115.54 0.06 0.17
60 123.24 0.08 0.20
80 130.89 0.09 0.23
100 138.50 0.10 0.27
120 146.06 0.11 0.30
Resistance
Thermometer
.
2
) 2 Meas 1 Meas (
3 Meas



 +
−