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Model 7701
Multiple channel operation
WARNING
Multiple channel operation should only be performed by experienced test engineers who
recognize the dangers associated with multiple channel closures.
Multiple channel operation provides independent control of switching module channels. When you close a
multiple channel, only the specified channel (or channels) will close. Other closed channels are not affected.
Multiple channel operation for the Model 7701 is summarized as follows:
•
For earlier versions of the Model 2700, multiple channel operation is not available from the front
panel (remote operation only).
•
For the Model 2750 and later versions of the Model 2700, the MULTI option of the CLOSE key can
be used to close a channel.
•
For the Model 2750 and later versions of the Model 2700, the MULTI option of the OPEN key can be
used to open a channel. The ALL option of the OPEN key opens all channels.
ROUT:MULT:CLOS <clist>
Close specified channels (unlisted channels
not affected).
ROUT:MULT:OPEN <clist>
Open specified channels (unlisted channels
not affected).
ROUT:MULT:CLOS?
Returns list of all closed channels.
ROUT:MULT:CLOS:STAT? <clist>
Query closed channels in list (1 = closed).
You can also use the following command to open all channels:
ROUT:OPEN:ALL
Open all channels.
Applications
WARNING
Multiple channel operation is required for the following applications. Multiple channel
operation should only be performed by experienced test engineers who recognize the
dangers associated with multiple channel closures.
Common-side 4-wire ohms measurements
When using 4-wire ohms measurements and system channel operation, up to 16 DUT can be tested by the
DMM. By using multiple channel operation and the user configurable screw terminals, up to 32 DUT can be
measured using 4-wire ohms. Such a test system is shown in
As shown in
, all 32 DUT are connected to a common metal bus. The bus is connected directly to
Input HI and Sense HI of the DMM via the user-configurable screw terminals. The 32 measurement chan-
nels can then be used to connect the other side of each DUT to Input LO and Sense LO of the DMM. Jumper
installation for this test system is shown in
For this application, channels 33 and 35 are to be controlled as follows:
•
Opening channel 33 connects Multiplexer 1 (channels 1 through 16) to Multiplexer 2 (channels 17
through 32). Channel 33 must remain open for all DUT tests.
•
Closing channel 35 connects a measurement channel (1 through 32) to the DMM Input. Channel 35
must remain closed for all DUT tests.