PPM–400ST Formaldehyde Meter Operation Manual
Limit 1 :
Lt=1
Default setting for PPM–400ST Formaldehyde Meter.
Limit 2 :
Lt=2
Glutaraldemeter
®
mode – do not use.
Limit 3 :
Lt=3
Used if the PPM–400ST Formaldehyde Meter is
regularly sampling concentrations of formaldehyde in
excess of 2ppm, allowing the instrument to sample at
more regular intervals than if the default Limit Setting
were used.
Note that when using Limit Setting 3 low concentration
readings are less accurate as some residual
formaldehyde from the previous sample may still be
present in the sensor.
Limit 4 :
Lt=4
Used in the “extended range”
PPM–400ST
Formaldehyde Meter. Please contact the manufacturer
regarding this setting as changing the limit to “4” may
require additional changes to the instrument settings
and hardware.
5.3 Data Retrieval
The PPM–400ST Formaldehyde Meter has sufficient
memory capacity to log the last 10 concentration
samples in both ppm and mg/m
3
.
Accessing the Data
1. Hold down the
$
button whilst turning the
instrument on. The instrument will display the
HEAt
message (as described in Section 5.1). Release all
the buttons.
2. Now press both
>
and
<
to view the saved data.
The display will briefly show
dAtA
to confirm this.
3. The display will then alternate between showing
the saved sample number and the saved
concentration in ppm. The samples are shown from
the most recent (
run0
) to the oldest (
run9
).
4. Use the
>
or
<
buttons to change the display to the
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