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Calibration in Standard Mode
pH operation in standard mode offers full function of
edge
®
pH
. This includes seven standard buffers
and two custom ones. Five pH buffers may be used for calibration.
The instrument should be recalibrated whenever:
• High accuracy and sensor verification are required.
• The pH electrode is replaced.
• At least once a week.
• After testing aggressive chemicals.
• If ”CAL DUE” is displayed on the third LCD line.
pH CALIBRATION
Every time you calibrate the instrument use fresh buffers and perform electrode maintenance as
required. It is advised to choose calibration buffers that bracket the sample pH.
Preparation
Pour small quantities of the buffer solutions into clean beakers. If possible, use plastic to minimize
any EMC interferences. For accurate calibration and to minimize cross‑contamination, use two
beakers for each buffer solution; one for rinsing the electrode and one for calibration. If you are
measuring in the acidic range, use pH 7.01 or 6.86 as the first buffer and pH 4.01 (or 3.00*) as the
second buffer. If you are measuring in the alkaline range, use pH 7.01 or 6.86 as first buffer and
pH 10.01 or 9.18 as the second buffer.
* pH 3.00 is only visible when using specific pH electrodes and will replace 4.01 pH buffer.
OPERA
TIONAL GUIDE
Procedure
Calibration can be performed using up to five calibration buffers. For accurate measurements, a
minimum of a three‑point calibration is recommended. The calibration buffer can be selected from
the calibration buffer list that includes the custom buffers and the standard buffers:
pH 1.68, 4.01 (pH 3.00), 6.86, 7.01, 9.18, 10.01 and 12.45.
Summary of Contents for HI 2002
Page 1: ...INSTRUCTION MANUAL pH...