Keithley 2701, Руководство пользователя

Страница: 65 / 478

2-10 Close/Open Switching Module Channels Model 2701 User’s Manual
Controlling the system channel
When a measurement channel is closed, a previous system channel (and, for a 4-wire
function, its paired channel) is first opened. The closed measurement channel becomes the
system channel. When a 4-wire function is selected, the paired channel for the system
channel also closes.
and keys
These front panel keys (Figure 2-3) can be used to select the next or previous
measurement channel as the system channel. If there are no measurement channels
available, one of the following messages will be briefly displayed when one of these keys
is pressed:
NO SCAN CARD — This message indicates that there are no switching modules (or
pseudocards) installed; both slots are empty.
NO MEAS CARD — This message indicates that none of the installed switching modules
(or pseudocards) have measurement channels. For example, the Model 7705 switching
module does not have any measurement channels. Those channels cannot be internally
connected to the DMM.
NOTE The and keys can also be used to open all channels in the mainframe.
Simply increment or decrement the channel number until there is no channel
displayed.
Figure 2-3
System channel operation — closing next or previous measurement channel
CLOSE key (SINGLE menu option)
The SINGLE menu option for the CLOSE key can be used to select a measurement
channel as the system channel (Figure 2-4). Perform the following steps to select the
system channel:
1. Press the CLOSE key. The “CLOSE:SINGLE” message will be displayed.
NOTE If the “CLOSE:MULTI” message is instead displayed when CLOSE is pressed,
it indicates that there are no measurement modules installed in the mainframe.
See “Multiple channel operation,” page 2-16, to close the channels of a non-
measurement module (i.e., Model 7705).
Close next
measurement
channel
Close previous
measurement
channel
2701-900-01.book Page 10 Wednesday, August 3, 2011 9:43 AM