Model 420 & 425 Flame Photometer
425 91 001
Issue 22
1
st
December 2016
ECN 1410 & 1932
- 44 -
Operating the Instrument
continued
6.2.2 Required Calibration
(
NB
Li must be in diluent if operating in Ref).
On initial start up the instrument requires a Calibration step after the Blanking
process. The instrument goes into calibrate mode with the "Cal"(s) flashing,
"Measure" off, and the most recent calibration values on the display.
The ‘Single’ and ‘Dual’ mode of operations both Calibrate in the same manner.
The preparation and presentation of standards in “Dual” are different for “Cont” and
“Peak”.
Continuous Mode.
(In Dual Mode standards can be
presented as individual elements and
each channel separately calibrated). The
channel(s) should be adjusted to desired
value(s) using '-' or '+'. When desired
value(s) are flashing introduce the
standard and then press 'Set' in any
order within 2 seconds of each other.
The user waits for readings to reach
what the user judges to be steady
plateau values and presses 'Set' on
each channel at the appropriate time to
confirm the values. As these presses of
'Set' are registered the displayed
readings are adjusted to calibration
values, the output is sent and the
instrument goes into measure mode with
"Measure" on and "Cal" off.
Peak Mode
(With Reference is Default Mode).
(In
Dual
Mode
both
Sodium
and
Potassium standards must be mixed and
presented as one solution as there is no
operator involvement in the calibration
sequence).
Each channel should be adjusted to
desired value using '-' or '+'. When desired
value is achieved press “Set” on that
channel and then modify the other channel
if necessary and introduce the calibration
sample IMMEDIATELY BEFORE pressing
'Set' on the second channel.
The “Peak” process starts on both
channels and readings are displayed.
Once the Peak algorithm has accepted the
values, and the displays on both channels
change to the calibrated values, the user
presses 'Set' on both channels and the
output is sent. The displays start flashing,
"Cal" goes out, "Measure" comes on and
the instrument is ready to measure.
