Calibration – YSI ProDSS User Manual
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Calibration
Figure 51 Calibrate pH 2- or 3-point
pH calibration 2- or 3-point
NOTE: If performing a 2- or 3-point calibration, one point should
be in buffer 7; however, the calibration points can be in any
order.
1. Perform steps 1-7 of the pH calibration 1-point procedure (
calibration 1-point on page 39
).
2. Rinse the sensor 2-3 times with a small amount of pH 4 or pH 10
buffer solution.
3. Rinse, then fill the calibration cup to the appropriate level with
the buffer solution (approximately 170 mLs) that is the same value
(pH 4 or pH 10) used to rinse the sensor.
4. Carefully immerse the sensors into the solution.
5. Allow at least one minute for temperature stabilization, then
select Calibration value.
6. Enter the pH buffer value that corresponds to the buffer
temperature reading (value may be located on pH buffer bottle).
7. Observe the actual measurement readings for stability (white line
on graph shows no significant change for 40 seconds), then select
Accept Calibration (
). “Ready for cal point 3” will be
displayed in the message area.
8. Select Finish Calibration for a 2-point calibration or repeat the 2-
or 3-point calibration procedure with the third buffer solution.
Figure 52 Calibrate ORP
ORP calibration
1. Obtain/prepare a standard with a known oxidation reduction
potential (ORP) value.
NOTE: YSI recommends Zobell solution.
2. Fill the solution to fill line 1 on the calibration cup (approximately
170 mLs).
3. Carefully immerse the sensors into the solution.
4. Push the
Cal
key, then select pH/ORP, then ORP.
5. Allow the temperature of the standard to stabilize then select
Calibration value.
6. Enter the ORP calibration value that corresponds to the measured
temperature reading (example: the value of YSI Zobell @ 20 �C is
237.5)
7. Observe the actual measurement readings for stability (white line
on graph shows no significant change for 40 seconds), then select
Accept Calibration (
). “Calibration successful!” will be
displayed in the message area.