Keithley KUSB-3116, Руководство по началу работы

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4
Wiring Signals
39
4
4
4
4
4
4
4
4
Note that since they measure the difference between the signals at the
high (+) and low (
−
) inputs, differential connections usually cancel
any common-mode voltages, leaving only the signal. However, if you
are using a grounded signal source and ground loop problems arise,
connect the differential signals as shown as
Figure 12 . In this case,
make sure that the low side of the signal (
−
) is connected to ground at
the signal source, not at the screw terminal panel, and do not tie the
two grounds together.
Figure 12: Connecting Differential Voltage Inputs from a Grounded Signal
Source to a Screw Terminal Panel
Grounded
Signal
Source
+
-
Analog In 0
Analog In 0 Return
E
s
Signal Source
Ground V
g1
It is recommended that
you use the Open
Layers Control Panel
applet to enable 10 k
Ω
of resistance to connect
the low side of channel
0 to analog ground (a
physical resistor is not
required). Refer to
page
16 for more information.
36
20
1
Screw Terminal Panel
Analog Ground