Thermo Fisher Scientific CyberScan PC 510 - Manual (Page 13)

Instruction Manual PC 510
9
5.4 Conductivity/TDS calibration
The PC 510 has 5 measuring ranges. You can calibrate 1 point each of the measuring ranges (up to 5
points). If you are measuring values in more than 1 range, make sure to calibrate each of the ranges
you are measuring. All new calibration data will over-ride existing stored calibration data for each
measuring range you calibrate.
• If you are measuring in ranges near to or greater than 20 mS (10 ppt), or near to or lower than 100
µS (50 ppm), calibrate the meter at least once a week to get specified ±1% Full Scale accuracy.
• If you are measuring in the mid-ranges and you washed the probe in de-ionised water and stored
it dry, calibrate the meter at least once a month.
• If you take measurements at extreme temperatures, calibrate the meter at least once a week.
5.4.1 Preparing for conductivity/TDS calibration
For best results, select a standard value close to the sample value you are measuring. Alternatively,
use a calibration solution value that is approximately 2/3 the Full-Scale value of the measurement
range you plan to use. For example, in the 0 to 1999 µS conductivity range, a 1413 µS solution is a
good solution for calibration.
See the table below for recommended calibration solution ranges.
Range
Indicator
Conductivity
Range
Recommended Calibration
Solution Range
TDS Range
Recommended Calibration
Solution Range
r 1 0.00 to 19.99 µS 6.00 to 17.00 µS 0.00 to 9.99 ppm 3.00 to 8.50 ppm
r 2 0.0 to 199.9 µS 60.0 to 170.0 µS 10.0 99.9 ppm 30.0 to 85.0 ppm
r 3 0 to 1999 µS 600 to 1700 µS 100 to 999 ppm 300 to 850 ppm
r 4 0.00 to 19.99 mS 6.00 to 17.00 mS 1.00 to 9.99 ppt 3.00 to 8.50 ppt
r 5 0.0 to 199.9 mS 60.0 to 170.0 mS 10.0 to 200 ppt 30.0 to 170.0 ppt
Calibration Solution Ranges
Temperature Coefficient: These meters are factory set to a temperature coefficient of 2.1 % per
°C.
For most applications this will provide good results. See Program P8.1 on page 37 to set the
temperature coefficient to different value. See Addendum 2, “Calculating Temperature Coefficients” to
determine the appropriate temperature coefficient for your solution.
Normalisation Temperature: The factory default value for normalisation temperature is 25
°C. If you
need to normalise to a value other than 25
°C, see Program P8.2 on page 38.
Do not reuse calibration solutions after calibration. Contaminants in the solution can affect the
calibration, and eventually the accuracy of the measurements. Use fresh calibration solution each time
you calibrate your meter.
All new calibration data will over-ride existing stored calibration data for each measuring range
calibrated.