PSM1700 PsimetriQ user manual
7-4
7.2 Datalog
PsimetriQ can store and display measurements recorded at
regular intervals over a time period. Each data record
consists of the elapsed time and up to four data values
selected by ZOOM. More than 8000 records can be stored
if one value is selected; more than 3000 if four values are
selected.
The actual interval between data points is governed by the
measurement speed and the datalog interval. PsimetriQ
stores the next available measurement after the datalog
interval has elapsed: the actual elapsed time is attached to
each datalog record, is displayed with the data on the
table or each graph, and returned with each record over
the communications (RS232, LAN or GPIB).
The data values may be stored to RAM or directly into non-
volatile memory as each value becomes available. The
non-volatile option is useful for acquiring data over long
periods, to prevent the loss of data in the event of a power
failure. Data that has been stored into RAM may be
subsequently transferred to non-volatile memory using the
PROG menu. In this mode the data may be viewed in real
time, as it is being acquired.
For high speed data acquisition, the datalog interval may
be set to zero so that each measurement is stored. The
measurement interval is controlled with the “speed” option
in the ACQU menu. Using the “window” option for speed
allows greater control of the measurement interval. In this
mode, the display flashes “DATALOG RUNNING” and only
shows the acquisition time. The minimum datalog interval
depends on the function but is typically 10ms.
Note that in all cases the measurement interval is
necessarily adjusted to be an integral number of cycles of
the measured waveform.