Metrohm 746 VA Trace Analyzer User Manual
Page 117
4 Introduction to the operation
746 VA Trace Analyzer / 747 VA Stand
4-32
2
Switch to dialog page "SEGMENT"
•
Press the yellow
appears with the program for measured value acquisition:
Method: CALCRV SEGMENT
DPASV
Instructions t/s Main parameters Auxiliary parameters
ДДДДДДДДДДДДД
ДДДДДДДДДДДДД ДДДДД
ДДДДД ДДДДДДДДДДДДДДДДДДДДДДДДД
ДДДДДДДДДДДДДДДДДДДДДДДДД
ДДДДДДДДДДДДДДДДДДДДДДДДД
ДДДДДДДДДДДДДДДДДДДДДДДДД
1 HMDE Drop size 4 Meas.cell normal
2 DPMODE U.ampl 50 mV t.meas 20.0 ms
t.step 0.10 s t.pulse 40.0 ms
3 MEAS 90.0 U.meas -600 mV
4 ØSTIR 5.0
5 SWEEP 7.0 U.start -600 mV U.step 6 mV
U.end -200 mV Sweep rate 60 mV/s
6 ØMEAS U.standby mV
7 END
Modify
column
Modify
line
Delete
instr.
Insert
instr.
Select
segment
Delete
segment
Plot
param.
Segment
name
•
The sequence of the segment
DPASV
is explained in brief in what follows:
Line 1
Switching on the HMDE (hanging mercury drop electrode)
Line 2
Selection of the measurement mode DP (differential pulse)
with voltage amplitude 50 mV, voltage step 0.1 s,
measurement time 20 ms and pulse time 40 ms
Line 3
Application of a measurement voltage of –600 mV for 90 s
for the enrichment of lead at the hanging mercury drop
Line 4
Switching off the stirrer and stabilization of the analysis
solution for 5 s
Line 5
Voltage sweep of –600 mV ... –200 mV with a
voltage step of 6 mV
Line 6
Switch off voltage and current measurement
Line 7
End of the segment (return to main program)
3
Switch to dialog page "SUBSTANCES"
•
Press the yellow
CES" appears with the parameters for evaluation of the substance lead.
Except for the characteristic voltage
U.verify
(–400 mV), these are
identical to those of the
TESTPb.mth
method and are not explained fur-
ther here (see section 4.2.3).
•
Press the softkey
< >> >
. The subpage of "SUBSTANCES" appears with
the parameters for calibration of the substance lead: