Troubleshooting and Maintenance
5
100 Operator’s Manual
41
Water Bath Temperature Probe Accuracy Test
The temperature probe can be tested using a high quality voltmeter
capable of at least four digit resolution and a known-temperature bath.
Both the voltmeter and the bath temperature must be traceable to a
known reference standard such as NIST.
1
Place the probe into a known-temperature water bath and allow
several minutes for the probe to equilibrate.
2
The resistance is measured by attaching the leads of the voltmeter to
the top and shank of the 1/4 inch phone plug.
3
Refer to the following table to find the resistance value of the probe
at the bath temperature. Temperatures between the values listed may
be interpolated.
4
Probes are interchangeable and manufactured with a tolerance of
± 0.2 °C. Probes found to be outside the tolerance of ± 0.2 °C should
be replaced.
Table 2
Probe Resistance Values
Temp.
Centigrade
Resistance
Ohms
Temp.
Centigrade
Resistance
Ohms
Temp.
Centigrade
Resistance
Ohms
-5.0
9530
24.0
2354
53.0
724.50
-4.0
9046
25.0
2252
54.0
697.90
-3.0
8586
26.0
2156
55.0
672.50
-2.0
8151
27.0
2064
56.0
648.10
-1.0
7741
28.0
1977
57.0
624.80
0.0
7355
29.0
1894
58.0
602.40
1.0
6989
30.0
1815
59.0
580.90
2.0
6644
31.0
1739
60.0
560.30
3.0
6319
32.0
1667
61.0
540.50
4.0
6011
33.0
1599
62.0
521.50
5.0
5719
34.0
1533
63.0
503.30
6.0
5444
35.0
1471
64.0
485.80