Hach ORBISPHERE 3654 Manuel D'utilisation De Base page 15

Maximum mode facilitates making measurements in bottles and cans. To search for a maximum
measurement value, press the MEAS button.
• The LCD first shows the message [run] for a few seconds, before displaying measurement values.
• After a 60 second measurement cycle, the instrument searches for two consecutive gas
measurements with less than 2% difference. When this condition occurs, the displayed value
freezes on the LCD (indicated by a blinking display), allowing you to note down or store the data.
The display remains frozen until you press the MEAS button to make a new measurement, or you
select normal measurement mode (as described in
5.3 Storing measurements in the instrument
The analyzer will store up to 500 gas concentration and temperature measurement values, labeled
by numbers 0 through 499, along with the current date and time of each measurement. You have the
choice of acquiring this information manually or automatically, as described below.
Note: Do not put the instrument into standby while it is in the process of storing data, otherwise the data values will
be lost.
Before storing measurements, you should verify the date and time settings of the instrument's
internal clock, as described in
5.3.1 Automatic data acquisition
Note: When the instrument is used to automatically store measurement data, all buttons except the POWER key
are disabled. If enough time elapses to store all 500 values, the instrument will return to normal measurement mode
and the buttons re-enabled.
Before starting automatic measurement storage, first select the sampling rate desired using the Hach
3654 program. Refer to
1. Put the instrument into standby (by pressing the POWER key).
2. Then hold down the STO button while switching the instrument back ON. The LCD displays the
message Sto for about one second.
3. Normal gas concentration measurements are displayed for about two minutes.
4. After two minutes the instrument displays the sample number (starting at 000), then the gas
concentration measurement value followed by [- - -] to indicate the measurement is being stored.
5. This storage sequence repeats automatically, at the rate specified by the Hach 3654 program
Sampling Rate menu. Values are stored sequentially in sample numbers 000 through 499.
Note: If you have not cleared previously stored values, the storage sequence automatically overwrites the older
values, as they are stored.
6. To end automatic storage, put the instrument into standby (by pressing the POWER key) while it
is in normal measurement mode and not while it is in the process of automatically storing data.
7. Switching ON again without holding down the STO button returns the instrument to measurement
mode.
Note: If you accidentally interrupt the automatic data storage by switching off the instrument while it is in the
process of storing a value, and you then attempt to download the stored values by the Hach 3654 program, you
will get a Windows Checksum Error message, and you will not be able to view the measurement data. If this
happens, go back to the instrument and manually log one more value. Refer to
on page 15. You can then download your original set of values to your PC.
5.3.2 Manual data acquisition
Note: You cannot store measurement data manually if the instrument has already been set up to store the data
automatically.
1. For the first measurement you wish to store, press the STO button once to display a sample
number. The default sample number is 000 (for first time access), or the last used memory
position where data was stored, incremented by a value of 1.
2. You can increase or decrease this number by pressing the Up/Down Arrow buttons within three
seconds.
Clock settings on page 28.
Automatic data acquisition - Setting sampling intervals
Measurement mode on page 21).
Manual data acquisition
on page 20.
English 15