Hanna Instruments edge PHM4092, Manual

Page: 21 / 44

Operational Guide 21
edge’s pH meter operation is confi gured by using the SETUP key with a pH probe
connected to the meter. The parameter-specifi c options will be seen inserted
into the menu. If Basic mode is “On”, the pH parameter list will not be displayed.
See Basic mode for a description of this operation before choosing how to
SETUP the meter.
Option Description Choices Default Basic mode
Basic Mode
When “On”, a limited set of
parameters and calibration
buff ers are available for
use.
Off or
On
Off Available
Information
Visual indication of buff ers
used, Probe Condition
and Response times are
determined and displayed
when calibration uses 7 and
4 and/or 10 pH buff ers.
Off or
On
On
Buff ers used, probe
conditions, and
response times are
not displayed.
First Custom
Buff er
When “On”, it permits the
user to enter a custom pH
buff er value to use during
electrode calibration.
Off or
value
Off Not Available
Second
Custom Buff er
When “On”, it permits the
user to enter a custom pH
buff er value to use during
electrode calibration.
Off or
value
Off Not Available
First
Calibration
Point Allows the user to choose
how the fi rst point in
calibration will be made.
Off set
or point
Off set
Not Available
(automatically uses
Off set).
Resolution
Allows the user to select
between 0.01 and 0.001 pH
resolution. 0.01 or
0.001
pH
0.01 pH
Not Available
(automatically uses
0.01 pH resolution).
Set Out Of
Calibration
Range
When set to “On”, a
measurement that is
outside the calibrated
range (buff ers used) will
trigger a warning message.
Off or
On
On
Not Available, No
Error messages
displayed.
pH Meter
Confi gurations
pH
Calibration
Calibration in Standard Mode
pH operation in standard mode off ers full function of edge pH ® . This includes
seven standard buff ers and two custom ones. Five pH buff ers may be used for
calibration.
The instrument should be recalibrated whenever:
•
High accuracy and sensor verifi cation 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.
Every time you calibrate the instrument use fresh buff ers and perform electrode
maintenance as required. It is advised to choose calibration buff ers that bracket
the sample pH.