Geokon 4911, Руководство по установке, Страница: 16 / 27

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3.4 Measuring Temperatures
All vibrating wire strain meters are equipped with a thermistor, which gives a varying resistance
output as the temperature changes. The white and green leads of the instrument cable are
normally connected to the internal thermistor.
The GK-403, GK-404, and GK-405 readout boxes will read the thermistor and display the
temperature in degrees C.
To read temperatures using an ohmmeter:
1) Connect an ohmmeter to the green and white thermistor leads coming from the strain meter.
(Since the resistance changes with temperature are large, the effect of cable resistance is
usually insignificant. For long cables a correction can be applied, equal to approximately
14.7 Ω per 1000 ft. (48.5 Ω per km) at 20 °C. Multiply these factors by two to account for
both directions.)
2) Look up the temperature for the measured resistance in Appendix B, Table 5 .