Thermo Scientific Orion Versa Star Pro, Руководство пользователя

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Appendix A

Channel Specific Settings and Features
Thermo Scientific Orion Versa Star Pro Meter User Manual

135
LogR Temperature Technology
The Versa Star Pro meter with pH/LogR measurement module allows direct temperature
measurement and temperature compensation using most standard glass-bulb pH electrodes
and patented digital LogR technology.
LogR technology is based on using the electrical resistance of the pH-sensing glass-bulb as the
temperature source. The logarithm of the resistance of the bulb varies almost linearly with the
reciprocal of the absolute temperature. Almost all standard glass-bulb pH electrodes exhibit a
similar decrease in resistance with increasing temperature. To maximize LogR performance
and accuracy, a ROSS Ultra or ROSS pH electrode is recommended.
LogR Resistance vs. Temperature Graph
LogR Temperature Accuracy
Table 1 – Two Point LogR Temperature Calibration, Average Error at pH 3 and pH 11
Electrode
Average
Temp. Error
0 to 25 °C
(°C)
Average
Temp. Error
Above 20 °C *
(°C)
Average Temperature
Compensation Error
0 to 25 ºC
(pH Units)
Average Temperature
Compensation Error
Above 20 °C *
(°C)
8202BN 0.36 0.10 0.004 0.001
8203BN 0.13 0.02 0.002 0.000
8235BN 0.04 0.14 0.000 0.002
8256BN 0.22 0.06 0.003 0.001
8272BN 0.23 0.06 0.003 0.001
9202BN 0.21 0.06 0.003 0.001
9203BN 0.20 0.10 0.002 0.001
9206BN 0.29 0.06 0.003 0.001
9207BN 0.16 0.07 0.002 0.001
9256BN 0.27 0.07 0.003 0.001
9272BN 0.22 0.06 0.003 0.001
* For 20 °C temperature compensation spans