1-28 Getting Started Model 2750 Multimeter/Switch System User’s Manual
Closing and opening channels — system channel operation
NOTE See Section 2 for details on closing and opening switching module channels.
NOTE The following discussion assumes a multiplexing switching module (i.e., Model
7700) installed in slot 1 of the mainframe. Switching module installation is cov-
ered in “Switching module installation and connections,” page 2-3.
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
System channel operation is used to connect input channels to the DMM of the Model
2750:
• For a 2-wire function (i.e., DCV), closing a system channel connects the input to
DMM Input of the Model 2750.
Figure 1-5 shows system channel 1 closed. For the Ω2 function, the resistance
(DUT) would be connected to DMM Input as shown Figure 1-5.
• 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 1-6 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. Figure 1-6 shows
how the DUT is connected to the DMM for the 4-wire function.
NOTE Figure 1-5 and Figure 1-6 show simplified schematics of the switching module.
They show a single switch closed to connect an input channel to the DMM. In
reality, multiple switching to 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.
Figure 1-5
Connection to DMM for 2-wire function (system channel 101 closed)
DMM
DUT
DMM
Switching Module Switching Module
HI
LO
HI
LO
Input
Ch 1
HI
LO
HI
LO
Input
Ch 1
2750-900-01.book Page 28 Wednesday, August 3, 2011 7:56 AM
To Next Page
Loading...
Need help?
General
