Dynasonics TFX Ultra Transit Time Flow Meters - Manual (Page 85)

Check the RTDs resistance values with an ohmmeter to make sure they are not “open” or “shorted”. See Table 20 for typical RTD
resistance values. Next check to ensure that incorrect “Cal Point” values were not entered inadvertently.
Heat Capacity of Water (J/g°C)
°C 0 1 2 3 4 5 6 7 8 9
0 4.2174 4.2138 4.2104 4.2074 4.2045 4.2019 4.1996 4.1974 4.1954 4.1936
10 4.1919 4.1904 4.1890 4.1877 4.1866 4.1855 4.1846 4.1837 4.1829 4.1822
20 4.1816 4.0310 4.1805 4.1801 4.1797 4.1793 4.1790 4.1787 4.1785 4.1783
30 4.1782 4.1781 4.1780 4.1780 4.1779 4.1779 4.1780 4.1780 4.1781 4.1782
40 4.1783 4.1784 4.1786 4.1788 4.1789 4.1792 4.1794 4.1796 4.1799 4.1801
50 4.1804 4.0307 4.1811 4.1814 4.1817 4.1821 4.1825 4.1829 4.1833 4.1837
60 4.1841 4.1846 4.1850 4.1855 4.1860 4.1865 4.1871 4.1876 4.1882 4.1887
70 4.1893 4.1899 4.1905 4.1912 4.1918 4.1925 4.1932 4.1939 4.1946 4.1954
80 4.1961 4.1969 4.1977 4.1985 4.1994 4.2002 4.2011 4.2020 4.2029 4.2039
90 4.2048 4.2058 4.2068 4.2078 4.2089 4.2100 4.2111 4.2122 4.2133 4.2145
Table 19: Heat capacity of water
STANDARD RTD (Ohms)
°C °F 100 Ohm 1000 Ohm
–50 –58 80.306 803.06
–40 –40 84.271 842.71
–30 –22 88.222 882.22
–20 –4 92.160 921.60
–10 14 96.086 960.86
0 32 100.000 1000.00
10 50 103.903 1039.03
20 68 107.794 1077.94
25 77 109.735 1097.35
30 86 111.673 1116.73
40 104 115.541 1155.41
50 122 119.397 1193.97
60 140 123.242 1232.42
70 158 127.075 1270.75
80 176 130.897 1308.97
90 194 134.707 1347.07
100 212 138.506 1385.06
110 230 142.293 1422.93
120 248 146.068 1460.68
130 266 149.832 1498.32
Table 20: Standard RTD resistance values
REPLACING OR RE-CALIBRATING RTDS
Page 85 March 2014