Xylem YSI ProDSS, Руководство пользователя

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39
Calibration
pH/ORP
pH Calibration 1-Point
NOTE: If performing a 1-point calibration, use buffer 7 (6.86) as
your calibration point for highest accuracy.
NOTE:
Observe the pH mV readings during calibration to
understand the condition and response of the pH sensor. In
buffer 7, pH mVs should be between -50 and +50. In buffer
4, the mVs should be a +165 to 185 away from the pH 7 mV
value. In buffer 10, the mVs should be a -165 to -185 away
from the pH 7 mV value. Ideal slope is -59 mV per pH unit.
1. Perform the “Calibration setup (pH, ORP, ISE, conductivity, turbidity,
and total algae sensors)” on page 33 ).
2. Fill the calibration cup to the appropriate level with pH 7 buffer
solution (or 6.86 if using NIST buffers).
3.
Carefully immerse the probe end of the sensors into the buffer
solution.
4.
Push the
Cal
key, then select
pH
or
pH/ORP
.
NOTE: If using a pH/ORP sensor, select pH/ORP , then pH .
5.
Allow at least one minute for temperature stabilization. The
Calibration value
will automatically be adjusted based on the
selected buffer set and temperature. Alternatively, the Calibration
value can be manually entered.
6. Observe the actual measurement readings for stability (white line
on graph shows no significant change for 40 seconds), then select
Accept Calibration ( Figure 51 ). “Ready for cal point 2” will be
displayed in the message area.
7. After calibrating to the first point, select Finish Calibration for
a 1-point calibration or continue on to the 2-3 point calibration
procedure (
“Calibration cup installation” on page 34 ).
Figure 51
Calibrate pH 1-point