Ph Calibration Notes - eXact pH+ Instruction Manual

• The meter will automatically recognize 5 types of pH buffer
solution (see USA/NIST series list below). Users can perform
1-point, 2-point (recommended), or 3-point calibration.
• Perform one-point
proceeding to two-point and three-point calibration.
• Use pH buffers for two-point and three-point calibration as in the
table below:
Calibration
1-point (1) 7.00
(1) 7.00
(2) 4.00 or 1.68
2-point
(1) 7.00
(2) 10.01 or 12.45
(1) 7.00
(2) 4.00 or 1.68
3-point
(3) 10.01 or 12.45
• To maintain the accuracy of the pH buffer standards, replace them
after fi ve (5) uses. To prevent contamination, NEVER pour used pH
Buffer solutions back into the original pH Buffer solution bottles.
• This pH probe was not designed to give accurate readings for
distilled or deionized water There are not enough ions present in
these waters for accurate detection.
• When testing purifi ed water like spring water or drinking water, it
will take longer for the readings to stabilize (typically 3-5 minutes)
because there are low levels of ions for the sensor to detect.
• DO NOT store the pH probe in distilled water. This will cause
permanent damage to the probe.
• pH Buffers for calibration should be selected based on
the measurement. 2-point (7.00 and 4.00) Calibration is
recommended for most applications.
• Avoid cross-contaminating the pH buffers. Rinse the pH probe
and blot excess water after each measurement.
• Do not rub or touch the pH glass bulb!
Important Operation Note: the eXact pH
engineered/designed for the nontechnical service person who requires
a quick and accurate (within ±0.05) on-site pH measurement. The test
methodology, if followed carefully, is this:
Perform 2-point calibration weekly and store pH probe in 4.00 pH Buffer
between measurements. During the week of use, each time you power ON
eXact pH meter, the pH should display between 3.97 and 4.03. This verifi es
+
the meter is still maintaining calibration. When display is <3.97 or >4.03.
discard the solution and pour a fresh pH 4.0 buffer solution and check
display again. Remove Probe Storage Cap and set aside with pH 4.00
Buffer solution. Rinse the pH probe with clean water, then proceed to pH
measurement. More frequent calibrations may be needed if testing solutions
in extreme temperatures or substantial changes in pH such as from 10 to 4.

PH CALIBRATION NOTES

calibration (7.00 buffer) fi rst before
USA Series
(pH)
exactph.com
NIST Series
(pH)
(1) 6.86
(1) 6.86
(2) 4.01 or 1.68
(1) 6.86
(2) 9.18 or 12.45
(1) 6.86
(2) 4.01 or 1.68
(3) 9.18 or 12.45
Smart Meter was especially
+
Recommended
LCD
Accuracy and
Icon
Range (pH)
Accuracy ≥ 0.1
Measurement
Range <9.00
Measurement
Range >9.00
Custom
Measurement
Range
13