Optical pH Sensors USER MANUAL OPERATING INSTRUCTIONS pH www.pyroscience.
Optical pH Sensors | User Manual Optical pH Sensors Document Version 1.09 The Optical pH Sensors are released by PyroScience GmbH Hubertusstrasse 35 52064 Aachen Germany Phone Fax Email Web +49 (0)241 5183 2210 +49 (0)241 5183 2299 info@pyroscience.com www.pyroscience.
Optical pH Sensors | User Manual TABLE OF CONTENT 1 Introduction ..................................................................................................................................... 5 2 Sensor Settings ............................................................................................................................... 6 2.1 Explanation of the Sensor Code ................................................................................................7 2.
Optical pH Sensors | User Manual 7 6.1 pH Measuring Principle .............................................................................................................. 20 6.2 Explanation of the Different pH Ranges ............................................................................. 21 6.3 Available sensors and read-out devices ............................................................................. 22 6.4 Pt100 Temperature Sensor Calibration ......................................
Optical pH Sensors | User Manual 1 INTRODUCTION PyroScience offers fiber-based and contactless optical pH sensors, as well as a number of combined sensors such as sensor vials for simultaneous measurements of temperature, oxygen and pH.
Optical pH Sensors | User Manual 2 SENSOR SETTINGS Each optical pH sensor comes with an individual Sensor Code, containing important information on adjustments for optimal sensor performance and pre-calibration of the respective sensor type. Therefore, it is important to enter the Sensor Code of the connected sensor into the Sensor Settings of the Pyro Workbench software.
Optical pH Sensors | User Manual 2.1 Explanation of the Sensor Code The pH sensors are delivered with an attached sensor code which must be entered in the Settings window. The following gives a short explanation about the information given in the sensor code. Example Code: SAE7 -532-205 SA: Sensor Type. Factory calibration values of the sensor types (PK7, PK8….) E: LED Intensity of the device 7: Amplification of the measurement signal 532 – 205: Pre-calibration values 2.
Optical pH Sensors | User Manual readings is activated. The compensation temperature will be displayed in the corresponding channel row of the main window. AquapHOx: The AquapHox devices have a temperature sensor included for automatic temperature compensation. The temperature sensor is factory 2-point calibrated. Pico-pH: The Pico-pH OEM module does not include an Pt100 temperature sensor. This sensor (Item No. TSUB21-NC) needs to be soldered on the device.
Optical pH Sensors | User Manual There are several general categories of salinity ranges to select in the Pyro Workbench software: Category Salinity [g/l] Conductivity [mS/cm] Ionic Strength [mM] Wastewater 0.5 - 1.5 1-3 10 - 30 Intermediate 1.5 - 5 3 - 10 30 - 100 Physiological 5 - 15 10 - 30 100 - 300 Seawater 15 - 40 30 - 80 300 - 800 For more accurate measurements it is possible to enter a known salinity [g/l] of the sample in the software.
Optical pH Sensors | User Manual 3 SENSOR CALIBRATION 3.1 General Informations The pH calibration has to be repeated periodically, depending on the individual application (e.g. required accuracy, temperature of the sample, life-time of the sensor, substances in sample). It is advisable to perform a 2-point calibration before every measurement using freshly prepared buffer solutions.
Optical pH Sensors | User Manual Please do NOT use commercially available buffer solutions and certified reference materials (CRMs) used for pH electrodes. These buffers (colored and uncolored) contain anti-microbial agents that will affect the sensor performance irreversibly. It is important to only use PyroScience buffer capsules or selfmade buffers with known pH and ionic strength for calibration (with advice from PyroScience). 3.1.
Optical pH Sensors | User Manual 3.2 Preparation of Calibration Standards For the calibration it is strongly recommended to use PyroScience pH buffer capsules with pH 2 (item no. PHCAL2) and pH 11 (item no. PHCAL11) • • pH 2 buffer are used for the first calibration point pH 11 is used for the second calibration point For this, open the capsule by holding both ends and pulling them apart. Dissolve the powder of the capsule in 100 mL demineralized water.
Optical pH Sensors | User Manual For the first calibration point, prepare a pH 2 buffer solution based using the PyroScience buffer capsules (item no. PHCAL2) or a custom calibration buffer. It is recommended to perform the calibration at the same temperature of the actual pH measurements. It is strongly recommended to perform calibration at conditions close to the environmental conditions during measurements. Ensure constant conditions during calibration.
Optical pH Sensors | User Manual 3.4 Second Calibration Point (basic pH) It is highly recommended to perform a 2-point calibration before every measurement. For pH Minisensor it is necessary to perform a 2-point calibration. For the second calibration point, prepare a pH 11 solution based on the PyroScience buffer capsule (item no. PHCAL11) or a custom calibration buffer.
Optical pH Sensors | User Manual 1. The end of the sensor lifetime is reached and the sensor needs to be replaced. 2. The sensor is connected to the wrong channel at the multi-channel FireSting pro 3. In case of sensor spots: the positioning of the optical fiber on the sensor spot is not correct. 4. The vessel wall is too thick in the case of sensor spots. In this case, please try to increase the LED intensity as maybe the vessel wall is too thick or the sensor is altered to a high extend.
Optical pH Sensors | User Manual 3.7 Advanced Calibration of Sensor Spots If sensor calibration is not possible due to a too large vessel for the pH buffer to reach the spot, it is possible to use a smaller vessel with a second spot from the same product batch for calibration. Use the identical optical fiber and the same optical channel from the FireSting pro as your measurement will be performed. It is possible that the accuracy of the measurement will be influenced due to this calibration method.
Optical pH Sensors | User Manual 4 STERILIZATION, CLEANING AND STORAGE 4.1 Cross Sensitivities Do not use any organic solvents, surfactant solutions or antimicrobial agents (which can be a compound commercial calibration buffers or certified reference materials (CRMs) used for pH electrode). The sensor may have cross-sensitivity to substances in your sample. Please contact us in doubt as irreversible damage of the sensor can occur with some compounds (e.g. surfactants). 4.
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Optical pH Sensors | User Manual 5 RELATED DOCUMENTS Related documents for more detailed instructions on fiber-optic read-out devices, software and optical sensors are available: • • • • • • manual manual manual manual manual manual for for for for for for logger software "Pyro Workbench" (Windows) multi-analyte meter FireSting pro the AquapHOx Loggers or Transmitters the OEM module Pico-pH(-SUB) optical temperature sensors optical oxygen sensors © PyroScience GmbH 19
Optical pH Sensors | User Manual 6 APPENDIX 6.1 pH Measuring Principle The optical pH sensor is based on the successful PyroScience REDFLASH technology. The sensor consists of a pH insensitive reference indicator and a pH sensitive luminescent dye. Both are excited with red-light (more precisely: orange-red at a wavelength of 610630 nm) and show bright luminescence in the near infrared (NIR, 760-790 nm).
Optical pH Sensors | User Manual 6.2 Explanation of the Different pH Ranges Optical pH sensors are sensitive to a pH range of 2-3 pH units. Sensors are offered for two different ranges for pH measurements. pH range 4.0-6.0 Item No. …-PK5 5.0-7.0 5.5-7.5 …-PK6 …-PK6.5 6.0-8.0 …-PK7 7.0-9.0 7.0-9.0 on pH total scale for seawater measurements …-PK8 …-PK8T Depending on the application it is important to choose the right version.
Optical pH Sensors | User Manual 6.
Optical pH Sensors | User Manual 6.4 Pt100 Temperature Sensor Calibration For precise absolute temperature readings, an optional 1-point calibration of the external temperature sensor is recommended. For this, check the reading of the external temperature Pt100 probe periodically in stirred water/water bath/incubator of known temperature at steady state. It is also possible to prepare a water-ice-mixture giving 0°C, where at least 50 mm of the Pt100 temperature probe tip is submerged.
Optical pH Sensors | User Manual 7 WARNINGS AND SAFETY GUIDELINES Before using PyroScience pH sensors, carefully read the instructions and user manuals for the respective PyroScience read-out device. The manuals are available for download on www.pyroscience.com Prevent mechanical stress (e.g. scratching) to the sensing surface at the tip of the temperature sensor! Avoid strong bending of the fiber-optic cables and the pH Minisensor.
Optical pH Sensors | User Manual CONTACT PyroScience GmbH Tel.: +49 (0)241 5183 2210 Hubertusstraße 35 Fax: +49 (0)241 5183 2299 52064 Aachen info@pyroscience.com Deutschland www.pyroscience.com www.pyroscience.