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Appendix A:  Thermistor Chart 

 

Thermistor Linearization using Steinhart and Hart Log Equation 

Tech Memo 91-03  Doc Rev 6-94, Geokon, Inc. 

Thermistor Type: YSI 44005, Dale #1C3001-B3, Alpha #13A3001-B3 

Basic Equation: 

T

A

B LnR

C LnR

=

+

+

1

273 2

3

(

)

(

)

.

 

where: 

T

 

=

 Temperature in 

°

C. 

 

LnR

 

=

 Natural Log of Thermistor Resistance 

 

A

 

=

 1.4051 

×

 10-3 

 

B

 

=

 2.369 

×

 10-4 

 

C

 

=

 1.019 

×

 10-7 

Note: Coefficients calculated over -50

°

 to +150

°

 C. span. 

Resistance versus Temperature Table 

 

 

Ohms  Temp Ohms Temp Ohms Temp Ohms Temp Ohms Temp 

 

201.1K -50 16.60K -10  2417 

+

30 

525.4 

+

70 

153.2 

+

110 

187.3K -49 15.72K  -9  2317  31  507.8  71  149.0  111 
174.5K -48 14.90K  -8  2221  32  490.9  72  145.0  112 
162.7K -47 14.12K  -7  2130  33  474.7  73  141.1  113 
151.7K -46 13.39K  -6  2042  34  459.0  74  137.2  114 
141.6K -45 12.70K  -5  1959  35  444.0  75  133.6  115 
132.2K -44 12.05K  -4  1880  36  429.5  76  130.0  116 
123.5K -43 11.44K  -3  1805  37  415.6  77  126.5  117 
115.4K -42 10.86K  -2  1733  38  402.2  78  123.2  118 
107.9K -41 10.31K  -1  1664  39  389.3  79  119.9  119 
101.0K 

-40 9796  0  1598  40 376.9 80 116.8 120 

94.48K -39  9310 

+

1535  41 364.9 81 113.8 121 

88.46K 

-38 8851  2  1475  42 353.4 82 110.8 122 

82.87K 

-37 8417  3  1418  43 342.2 83 107.9 123 

77.66K 

-36 8006  4  1363  44 331.5 84 105.2 124 

72.81K 

-35 7618  5  1310  45 321.2 85 102.5 125 

68.30K 

-34 7252  6  1260  46 311.3 86  99.9 126 

64.09K 

-33 6905  7  1212  47 301.7 87  97.3 127 

60.17K 

-32 6576  8  1167  48 292.4 88  94.9 128 

56.51K 

-31 6265  9  1123  49 283.5 89  92.5 129 

53.10K 

-30 5971 10 1081 50 274.9 90  90.2 130 

49.91K 

-29 5692 11 1040 51 266.6 91  87.9 131 

46.94K 

-28 5427 12 1002 52 258.6 92  85.7 132 

44.16K 

-27 5177  13 965.0 53 250.9 93  83.6 133 

41.56K 

-26 4939  14 929.6 54 243.4 94  81.6 134 

39.13K 

-25 4714  15 895.8 55 236.2 95  79.6 135 

36.86K 

-24 4500  16 863.3 56 229.3 96  77.6 136 

34.73K 

-23 4297  17 832.2 57 222.6 97  75.8 137 

32.74K 

-22 4105  18 802.3 58 216.1 98  73.9 138 

30.87K 

-21 3922  19 773.7 59 209.8 99  72.2 139 

29.13K 

-20 3748  20 746.3 60 203.8 100 70.4 140 

27.49K 

-19 3583  21 719.9 61 197.9 101 68.8 141 

25.95K 

-18 3426  22 694.7 62 192.2 102 67.1 142 

24.51K 

-17 3277  23 670.4 63 186.8 103 65.5 143 

23.16K 

-16 3135  24 647.1 64 181.5 104 64.0 144 

21.89K -15 

3000 25 

624.7 65 176.4 105 62.5 145 

20.70K 

-14 2872  26 603.3 66 171.4 106 61.1 146 

19.58K 

-13 2750  27 582.6 67 166.7 107 59.6 147 

18.52K 

-12 2633  28 562.8 68 162.0 108 58.3 148 

17.53K 

-11 2523  29 543.7 69 157.6 109 56.8 149 

        

55.6 

150 

  

Summary of Contents for LVRA1230B

Page 1: ...thout the written consent of Geokon Inc The information contained herein is believed to be accurate and reliable However Geokon Inc assumes no responsibility for errors omissions or misinterpretation The information herein is subject to change without notification Copyright 1995 2006 2008 by Geokon Inc Doc Rev F 04 08 ...

Page 2: ......

Page 3: ...re are no warranties except as stated herein There are no other warranties expressed or implied including but not limited to the implied warranties of merchantability and of fitness for a particular purpose Geokon Inc is not responsible for any damages or losses caused to other equipment whether direct indirect incidental special or consequential which the purchaser may experience as a result of t...

Page 4: ......

Page 5: ... INSTALLING THE SENSORS 3 2 4 THE NEXT STEP IS TO CONNECT THE TWO VENT LINES 3 2 5 THE NEXT STEP IS TO FILL THE LIQUID LINE 3 2 6 THE CHAMBERS SHOULD NOW BE FILLED 4 3 CALIBRATION 4 4 TAKING READINGS 4 5 CORRECTIONS FOR TEMPERATURE CHANGES 6 6 TROUBLESHOOTING 7 7 SPECIFICATIONS 7 APPENDIX A THERMISTOR CHART 8 APPENDIX B TYPICAL CALIBRATION SHEET 9 ...

Page 6: ...ID LEVEL SENSOR PRINCIPLE OF OPERATION 1 FIGURE 2 INSTALLATION DETAILS 2 FIGURE 3 DENSITY P OF PURE WATER AS A FUNCTION OF TEMPERATURE AND PRESSURE INTENSITY 6 THERMISTOR LINEARIZATION USING STEINHART AND HART LOG EQUATION 8 RESISTANCE VERSUS TEMPERATURE TABLE 8 ...

Page 7: ......

Page 8: ......

Page 9: ...at any one of the chamber locations causes an apparent rise or fall of the water level in that chamber leading to a greater or lesser buoyancy force on the weight and an decrease or increase of tension and frequency of vibration in the vibrating wire A very high resolution accuracy of the order of 0 07mm can be attained A vent line connecting all the transducer elements and the space above the liq...

Page 10: ...hen all brackets have been installed the chambers should be attached using the three threaded rods and nuts supplied Tighten one nut against the base of the chamber and use the other two nuts one on either side of the bracket Level by placing a spirit level on the chamber cylinder and then adjust the level with the nuts on the threaded rods that pass through the brackets The unit must be within 1 ...

Page 11: ...ow line up the holes in the chamber with the screw holes in the cap Gently lower the cap into the chamber being careful not to jar it as the O ring comes into contact with the tube When the cap is all the way in place put the three screws in and tighten them Do not over tighten Repeat this procedure for all the chambers 2 4 The next step is to connect the two vent lines The purpose of the chamber ...

Page 12: ... supply reservoir can be disconnected To prevent tampering with the liquid level the handle should be removed form the filling valve The plug on the end of the chamber vent line at the first chamber can now be replaced The desiccant chamber can be attached to the open end of the transducer vent line The sensor operation should be confirmed now by taking readings on all sensors and calculating the ...

Page 13: ... Ref 7163 0 002852 2 7858 0 002856 3 7967 0 002808 4 8028 0 002852 Subsequent readings on the chambers are as follows Chamber Reading 1 Ref 7118 2 7813 3 8628 4 7637 The changes in elevation of Chambers 2 3 and 4 are a Chamber No 2 EL2 R12 R02 G2 R11 R01 G1 7813 7858 0 002856 7118 7163 0 002852 0 1285 0 1283 0 0002 No Movement b Chamber No 3 EL3 R13 R03 G3 R11 R01 G1 8628 7967 0 002808 7118 7163 0...

Page 14: ...nge of the sensor The following equation is used to correct for temperature density changes H R1 R0 G SG where SG is the specific gravity of the fluid water at the measurement temperature Density and Compressibility Density is defined as the mass per unit volume and it depends upon the temperature and pressure intensity The density of pure water is given in Figure 3 Figure 3 Density p of pure wate...

Page 15: ... c If resistances are within nominal and no readings are obtainable on any transducer the readout is suspect and the factory should be consulted d If all resistances are within nominal and no readings are obtainable on any transducer the readout is suspect and the factory should be consulted 2 If cuts or shorts are located the cable may be splices in accordance with recommended procedures 7 Specif...

Page 16: ...75 42 353 4 82 110 8 122 82 87K 37 8417 3 1418 43 342 2 83 107 9 123 77 66K 36 8006 4 1363 44 331 5 84 105 2 124 72 81K 35 7618 5 1310 45 321 2 85 102 5 125 68 30K 34 7252 6 1260 46 311 3 86 99 9 126 64 09K 33 6905 7 1212 47 301 7 87 97 3 127 60 17K 32 6576 8 1167 48 292 4 88 94 9 128 56 51K 31 6265 9 1123 49 283 5 89 92 5 129 53 10K 30 5971 10 1081 50 274 9 90 90 2 130 49 91K 29 5692 11 1040 51 2...

Page 17: ...9 Appendix B Typical Calibration Sheet Sample Calibration sheet Note that the Volume Factor K is used to convert the Calibration factor C into the Calibration Factor G ...

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