Fluke NetDAQ 2645A - Manual (Page 19)

Overview
Introduction
1
1-3
Introduction 1-1.
The 2640A and 2645A NetDAQ  Networked Data Acquisition Units are
20-channel front ends that operate in conjunction with NetDAQ Logger for
Windows (hereafter known as NetDAQ Logger) to form a data acquisition
system.
The instruments measure dc volts, ac volts, Ohms, temperature, frequency, and dc
current. Temperature measurements use thermocouples or resistance-temperature
detectors (RTDs). To measure other parameters, use an appropriate transducer.
The instrument also includes ten computed channels for custom calculations
based on measured values.
The NetDAQ instruments scan the 20 analog channels in sequence and calculate
the values for the ten computed channels. Interval timers, alarm conditions, and/or
an external signal input can trigger scans. The NetDAQ Logger software
configures and controls up to 20 instruments via an Ethernet connection. The
software provides the means to view scan data and log it into files.
The 2640A and 2645A instruments (Figure 1-1) are identical in operation and
appearance, and vary only in emphasis. The 2640A emphasizes precision and
supports up to 100 measurements per second, with 5 ½ digits of resolution, .02%
accuracy, and 150-volt common mode voltage (300 volts on channels 1 and 11).
The 2645A emphasizes increased measurement speed supporting up to 1000
measurements per second, with 4 ½ digits of resolution, 0.04% accuracy, and 50-
volt common mode voltage. See Appendix A for instrument specifications.
NetDAQ
NETWORKED DATA ACQUISITION UNIT
COMM DIO MON
ENTER
CAL
ENABLE
REM SCAN
MON
V DC
CH
Figure 1-1. 2640A/2645A NetDAQ Networked Data Acquisition Units