Arbiter Systems 931A, Operation Manual

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this data. Harmonic data uses more memory space than Standard
data. One record of Harmonic data occupies 945 bytes of memory.
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Waveform data includes Standard data, Harmonic data, plus a
record of waveforms present on Channel 1 and 2. Press the LOG
DATA key, while displaying waveforms, to record waveform data.
Waveform data recording uses the most memory of any of the four
data types. One record of Waveform data occupies 1,425 bytes of
memory.
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3-phase data includes all the data presently on the 3-phase display.
One record of 3 phase data occupies approximately 366 bytes of
memory.
Each record in the same data file contains the same set of parameters.
Changing the data type after logging data causes the Model 931A to create
a new file, with its own header and associated set of records. Even with
custom record definitions, new files with record structures are started when
pressing the log data key after changing the display.
B.3.1.2 Custom
Users may program custom record structures from the front panel or
through the RS232 port. Custom data records allow the operator to store
only the parameters of interest, maximizing the number of data records
stored in extended memory. Defined by a 32-bit word, each bit of the word
defining the record corresponds to a particular data parameter. When
recalling custom data records, only the parameters that are part of the
custom record will be updated. All other parameters will be recalled from
the header of the logged file.
There is a direct relationship between the active display and the
collected data. When harmonics, waveform or three phase data are selected
for storage the respective display must be active.
B.3.1.3 Custom Data Setup
See Section B.3.4 for details on setting up the custom data feature. Unless
the Model 931A has an extended memory option installed, there will not
be an opportunity to setup custom data, as the Auto-Log Setup is added
as a selection item on the main menu.
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