Instruction manual

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The calibration solution could be the sample water itself. The concentration of PTSA in the
sample water can be determined with using an offline fluorometer like Pyxis SP-900, or
calculated from the concentration of any species in the sample water such as polymer,
phosphate, or molybdate.
The Probe Configurator displays the real-time PTSA concentration when the AutoRefresh
button is checked. The real-time PTSA is plotted in the Measurement Chart page.
Figure 6. Real-time PTSA display.
5.2.3. 4-20 mA Output Setup
The default setup is 20 mA output at 200 ppb PTSA. Fill in a value between 20 and 300 ppb
and click the mA2ppb button to reset the 4-20 mA output range. If this range is reset to
100 ppb, the probe will output 20 mA at 100 ppb, 12 mA at 50 ppb, and 4 mA at 0 ppb.
5.3. Calibration on the Controller
If the probe is set to output 20 mA at 200 ppb, the controller should be set up to convert 20
mA to 200 ppb and 4 mA to 0 ppb correspondingly. Optionally, the probe can be calibrated
by changing the conversion factor on the controller without being undergone the zero point
and slope calibration steps.
For example, if the probe outputs 10 mA in a 120 ppb standard solution, calculate this value
(z) according to:
z = (120 ppb  20 mA)/(10 mA – 4 mA) = 400 ppb.