Accumet AP85 Instruction Sheet

Accumet AP85 Instruction Sheet Manual pdf 7 page image

13124. Press CAL/MEAS to enter pH calibra-tion mode. The CAL indicator lights.The primary display will show themeasured reading while the smallersecondary display will indicate thepH standard buffer solution.See figure5. Wait for the measured pH value tostabilize. If the READY indicator hasbeen activated (set up programP3.1—see page 28), the READYannunciator lights when the readingis stable.6. Press ENTER to confirmcalibration. The meter is nowcalibrated to the current buffer.The lower display scrolls throughthe remaining buffer options.• If you are performing a multipointcalibration, go to step 7.• If you are performing a one-pointcalibration, go to step 9.7. Rinse the electrode with deionizedwater or a rinse solution, and dip inthe next pH buffer.8. Follow steps 5 to 8 for additionalcalibration points.9. When calibration is complete,press CAL/MEAS to return to pHmeasurement mode.See figureNotesTo exit from pH Calibration mode without confirming calibration, DO NOT pressENTER in step 6. Press CAL/MEAS instead.If the selected buffer value is not within ±1.0 pH from the measured pH value: theelectrode and buffer icon blink and the ERR annunciator appears in the lower leftcorner of the display.To limit the number of pH buffer values available during calibration, see Set-upprogram P3.2 on page 29.To select USA or NIST buffer sets, see Set-up program P3.3 on page 30.CCBBConductivity and TDS calibrationYou can calibrate up to 5 conductivity or TDS points, using a maximum of one pointper range (listed below):Range Conductivity: TDS:R1 0.00-19.99 μS 0.00-9.99 ppmR2 0.0-199.9 μS 10.0-99.9 ppmR3 0-1999 μS 100-999 ppmR4 0.00-19.99 mS 1.00-9.99 pptR5 0.0-199.9 mS 10.0-199.9 pptIf you are measuring values in more than one range, make sure to calibrate each ofthe ranges you are measuring. All new calibration data will over-ride existing storedcalibration data for each measuring range you calibrate.• If you are measuring in ranges near to or greater than 20 mS (10 ppt), or near toor lower than 100 μS (50 ppm), calibrate the meter at least once a week to getspecified ±1% full scale accuracy.• If you are measuring in the mid ranges and you rinsed the probe in deionizedwater and stored it dry, calibrate the meter at least once a month.• If you take measurements at extreme temperatures, calibrate the meter at leastonce a week.Preparing for conductivity/TDS calibrationFor best results, select a calibration standard value close to the sample value youare measuring. Alternatively, use a calibration solution value that is approximately2⁄3 the full scale value of the measurement range you plan to use. For example,in the 0 to 1999 μS conductivity range, use a 1413 μS solution for calibration.See the table below for recommended calibration solution ranges:4.3Temperature coefficient: This meter is factory set to a temperature coefficientof 2.1% per °C. For most applications this will provide good results. SeeProgram P8.1 on page 39 to set the temperature coefficient to a different value.See Appendix 3, “Calculating Temperature Coefficients” on page 49 to determinethe appropriate temperature coefficient for your solution.Normalization temperature: The factory default value for normalization temperatureis 25°C. If you need to normalize to a value other than 25°C, see Program P8.2 onpage 40.CONTINUED ON NEXT PAGEConductivity Recommended TDS RecommendedRange Cal. Solution Range Range Cal. Solution Range0.00-19.99 μS 6.00 to 17.00 μS 0.00-9.99 ppm 3.00 to 8.50 ppm0.0-199.9 μS 60.0 to 170.0 μS 10.0-99.9 ppm 30.0 to 85.0 ppm0-1999 μS 600 to 1700 μS 100-999 ppm 300 to 850 ppm0.00-19.99 mS 6.00 to 17.00 mS 1.00-9.99 ppt 3.00 to 8.50 ppt0.0-199.9 mS 60.0 to 170.0 mS 10.0-199.9 ppt 30.0 to 170 pptNOTE:1000 μS = 1 mS1000 ppm = 1 ppt