Closing And Opening Channels - System Channel Operation - Keithley 2701 User Manual

1-32 Getting Started
Closing and opening channels — system channel operation
NOTE
NOTE
System channel operation is used to connect input channels to the DMM of the
Model 2701:
•
•
NOTE
Figure 1-4
Connection to DMM for 2-wire function (system channel 101 closed)
HI
Ch 1
LO
See Section 2 for details on closing and opening switching module channels.
The following discussion assumes a multiplexing switching module (i.e.,
Model 7700) is installed in slot 1 of the mainframe. Switching module installa-
tion is covered in
tions," page 2-4).
An alternative to installing a switching module is to assign slot 1 as a
pseudocard using remote programming. The instrument will operate as if a
switching module is installed in slot 1. To "install" a 7700 pseudocard in slot 1,
send the following command:
SYST:PCAR1 C7700
For a 2-wire function (i.e., DCV), closing a system channel connects the input to
DMM Input of the Model 2701.
shows system channel 1 closed. For the Ω2 function, the resistance
Figure 1-4
(DUT) would be connected to DMM Input as shown
For a 4-wire function (i.e., Ω4), a channel pair is connected to the DMM when a
system channel is closed. The system channel is connected to DMM Input and the
paired channel is connected to DMM Sense.
Figure 1-5 shows system channel 6 closed. For a 4-wire function, the paired chan-
nel also closes. For the Model 7700, channels 1 through 10 are paired to channels
11 through 20. When channel 6 is closed, channel 16 also closes.
how the DUT is connected to the DMM for the 4-wire function.
Figure 1-4 and Figure 1-5
They show a single switch closed to connect an input channel to the DMM. In
reality, multiple switching is used to make proper connections to the DMM.
However, for system channel operation, the user need not be concerned about
which switches in the module close.
Switching Module
DMM
Input
Section 2 (see "Switching module installation and connec-
show simplified schematics of the switching module.
HI
HI
Ch 1
DUT
LO
LO
Model 2701 User's Manual
Figure 1-4.
Figure 1-5
Switching Module
DMM
Input
shows
HI
LO