Chapter 2
Installing and Configuring the DAQCard-700
2-4
ni.com
Analog Input Mode
The DAQCard-700 has two input modes: RSE and DIFF. RSE input mode
provides 16 channels. DIFF input mode provides eight channels. Table 2-2
describes these modes.
While reading the following paragraphs, you may find it helpful to refer
to the
Connecting Analog Input Signals
section of Chapter 3,
, which contains diagrams showing the signal paths for the
two modes. These two modes are software-selectable.
RSE Input Mode (16 Channels, Default Setting)
RSE input mode means that all input signals are referenced to a common
ground point that is also tied to the DAQCard-700 AI ground. The RSE
configuration is useful for measuring floating signal sources. See the
section of Chapter 3,
, for more
information. With this input configuration, the DAQCard-700 can monitor
16 different AI channels.
Considerations for using the RSE input mode are discussed in Chapter 3,
. Notice that in this mode, the return path of the signal
is analog ground at the connector through the AIGND pin.
Table 2-2.
Analog Input Modes for the DAQCard-700
Analog Input
Modes
Description
RSE
Referenced single-ended mode provides
16 single-ended inputs referenced to analog ground
(default setting).
DIFF
Differential mode provides eight differential inputs
with the positive (+) input of the instrumentation
amplifier tied to channels 0, 1, 2, 3, 4, 5, 6, or 7 and
the negative (–) input tied to channels 8, 9, 10, 11,
12, 13, 14, or 15, respectively, thus choosing channel
pairs (0, 8), (1, 9), (2, 10), (3, 11), (4, 12), (5, 13),
(6, 14), or (7, 15).