Scanning And Logging; Interface - Fluke NetDAQ 2640A User Manual

Designate one instrument in the group as the Master and the others as Slaves. The
Master controls scanning operations, including the scan intervals and method of
scan triggering. You can create only one group instrument.

Scanning and Logging

When a scan is triggered, the instrument scans the 20 analog channels and
calculates the 10 computed channels. It stores the resulting time-stamped data in a
scan record. Scans can be triggered from several sources:
Interval Trigger, where an elapsed interval timer triggers a scan.
External Trigger, where an external input (ground or logic low) applied to the
instrument TI (Trigger In) line triggers a scan.
Alarm Trigger, where a channel going into alarm status a scan.
NetDAQ Logger obtains scan records from the instruments and logs the data into
files. Each scan record written in the data file consists of a timestamp, values from
all configured analog channels and computed channels, the alarm states, the
digital I/O line status, and the count of the totalizer.
RS-232 Interface
The instruments include an RS-232 port for calibration and factory procedures;
the RS-232 port is not used for instrument control or scan data collection. The
NetDAQ Service Manual (PN 942615) describes calibration and factory
procedures that use the RS-232 port. See also "Calibration" in Chapter 6 of this
manual.
Overview
Host Computer Requirements
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