AMI Analyzer Manual
Communications
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range but one up, i.e. ten times the current range (unless the output range is 25%). Every 32 data points,
various internal parameters including the time and date are stored as well. If the memory capacity is
exceeded, the unit will overwrite the oldest data and keep on storing data in a circular fashion so that always
the most recent set of data points can be retrieved.
Note that since the unit only stores the output range every 32 data points, if you change the output range
this won’t be recorded until the next time it stores this value, but the reading of course will change
immediately. This means that there will be up to 32 data points with apparently the wrong value stored.
We recommend that if you do change the output range you clear the data so that no confusion can arise.
You can download the stored data by pressing the “Download Data” button. It may take a couple of minutes
to get it all, and the progress of this process is shown in a color bar, in traditional Windows style, though
unlike most Windows programs the length of the bar does in fact correspond with the amount of data
already retrieved.
Once the data is retrieved, it will be displayed in tabular form. It is automatically saved as an Excel™
compatible “CSV” format for subsequent analysis, so when you press the graph button the program opens a
dialog box which allows you to graph any of the stored files – the latest one will of course be the most recent
one. Double click it and the graph will appear. In the graph display you can zoom into data by clicking the
“Zoom In” button, and zoom out by clicking the “Zoom out” button.
The analyzer can be left to overwrite the old data by itself, or else it can be told to start again at the
beginning by pressing the “Clear Data” button.
The chart shows the oxygen reading, the average power supply voltage, the minimum power supply voltage
over each 32 data points, and the average temperature.
Power and Brownout history
The analyzer stores the times it was powered up, and records how many memory errors it ran into when it
did so. (It can’t store times it lost power!) The last ten times it was powered up can be displayed by clicking
the “Power History” button. The first column shows the number of data errors it saw, and this should always
be “00”. If it isn’t it implies that there is something wrong with the hardware and the unit should be
returned to AMI for repair. (The unit stores its configuration data in four separate locations, so that any one
memory error won’t affect its operation).
The “Brown Out” button shows times the power supply voltage dropped below 8.5V and came back above
that point again. This is useful in debugging the battery and solar panel power circuits often used in the
field.
