64
SECTION 3.4
MONITOR>>HIGH SPEED
control, and then click the “Set Span” button. A dialog will
prompt to confirm the selection.
NOTE: The pressure standard MUST have an accuracy of
at least .005% of the full scale value of the DXD being cali-
brated to maintain advertised accuracy of the DXD.
Gauge or Digital Indicator: Select the address of the trans-
ducer to which the span should be applied via the “DXD
Address” control in the upper left corner of the window. Apply
the span pressure to the transducer. Specify the span pressure
in the “Span Pressure” control, and then click the “Set Span”
button. A dialog will prompt to confirm the selection.
NOTE: The pressure standard MUST have an accuracy of
at least .005% of the full scale value of the DXD being cali-
brated to maintain advertised accuracy of the DXD.
The high-speed monitor window, shown in Figure 15, allows
monitoring of the pressure of a single DXD pressure trans-
ducer at the maximum possible rate. Access this window
via menu selection Monitor>>High Speed. When first enter-
ing this window, the pressure trend from the transducer
at address one updates the chart, if a transducer exists at
address one. The “Serial Number” shows “No Response!”
in red text if there is no response from the transducer at
the specified address. Insure that the address selected is
matched to the address in the targeted DXD.
The rate of retrieval of new values from the transducer
depends on how many processes are running on the com-
puter and consuming resources; interrupts, such as mouse
movements and clicks; and settings for update rate and baud
rate of the DXD pressure transducer. The transducer alone
can generate an update every 15 milliseconds. Factoring in
the overhead of communications through the serial port and
into the Windows operating environment, sample intervals to
file have been benchmarked at 17 milliseconds.
The current communication properties are shown at the
bottom right of the window. They are shown in order of com-
munication port (COM1), baud rate (115200), parity (Even),
number of data bits (7), and number of stop bits (1).
Figure 15