SCXI-1305 Installation Guide
4
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To ground-reference a floating signal for each channel, use the switch
settings shown in Table 1. Each channel has one switch with two positions
as follows:
•
Use the F position with floating signal sources. Setting one of these
switches to the F position connects a 100 k
Ω
resistor between the
negative input for the channel and analog ground. This resistor
supplies the necessary reference to ground for the channel. Do
not
use
this position with the SCXI-1120/D, SCXI-1121, SCXI-1125, or
SCXI-1126.
•
Use the G position with ground-referenced sources. Setting the switch
to the G position disconnects the resistor from the signal path. Always
use this position on the SCXI-1120/D, SCXI-1121, SCXI-1125, and
SCXI-1126.
Refer to Figure 2 for the floating and ground-referenced signal
configuration switch locations.
Table 1.
Floating and Ground-Referenced Signal Configuration
Switch Position
Description
References floating signals to
ground.
Disconnects ground-reference
resistor; use for signals that are
already ground-referenced
(factory setting). This is the
SCXI-1120/D, SCXI-1121,
SCXI-1125, and SCXI-1126
position.
F
G
F
G
