14
SYSTEM SETUP
The System Setup menu allows the user to customize the user interface, view meter information, set the
external serial communication interface and to restore the manufacturer settings.
Accessing System Setup
• Press
while in
Measure
mode.
• Press
. The system setup options will be displayed on
the LCD.
To access a System Setup option:
• Use
or
to highlight the desired option.
• Press
to access the selected option.
The following is a detailed description of the System Setup option screen:
Beeper
This option allows the user to turn an acoustic warning signal on
or off. This function can be used to signal 4 different events: a
stable signal, an alarm state, when every key is pressed or when
an incorrect key is pressed. Enable (or disable) the Beeper for
these events. Disabling the Beeper will stop audible signals.
67
∆
E
- the difference of potential from the electrode;
S
- the electrode slope, determined in a previous
calibration;
f
- the stoichiometric ratio between sample and
standard;
where:
C
SAMP
- the sample concentration;
C
STD
- the standard concentration;
V
SAMP
- the sample volume;
V
STD
- the standard volume;
V
ISA
- ISA volume
where:
C
SAMP
- the sample concentration;
C
STD
- the standard concentration;
V
SAMP
- the sample volume;
V
STD
- the standard volume;
V
ISA
- ISA volume;
∆
E
- the difference of potential from the electrode;
S
- the electrode slope, determined in a previous
calibration;
f
- the stoichiometric ratio between sample and
standard;
Example 1
You have sulfide samples and you are adding
Ag
+
. The reaction is:
One mole sulfide sample reacts with 2 moles silver standard (
f
=
1
/
2
).
Example 2
You have sulfide samples and you are adding
Pb
2+
. The reaction is:
One mole sulfide sample reacts with 1 mole lead standard (
f
= 1).
Analyte Addition and Analyte Subtraction
Analyte Addition and Subtraction are variations of the previous two methods.
With Analyte Addition,
sample (analyte) is added
to an Ion standard being measured. The standard and
sample contain the same Ion. mV are taken before and after the sample addition. From the mV the analyte
concentration is determined.
With Analyte Subtraction,
sample (analyte) is added to an Ion standard
being measured. The analyte reacts
with the measured Ion in a known manner thus removing measured ions from the solution. From the change
in mV the concentration of the analyte is determined.
S
2-
+ 2
Ag
+
→
Ag
2
S
S
2-
+
Pb
2+
→
PbS
C
SAMP
=
C
STD
·
V
STD
·
(
V
STD
+
V
SAMP
+
V
ISA
)·10
∆
E
-
(
V
STD
+
V
ISA
)
(
V
STD
+
V
ISA
)
V
SAMP
S
C
SAMP
=
f
·
{
(
V
STD
+
V
ISA
)
-
[
1 +
(
V
STD
+
V
ISA
)
]
·10
∆
E
}
·
(
C
STD
·
V
STD
)
V
SAMP
V
SAMP
V
STD
+
V
ISA
S
