Keithley 7707, User Manual

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6
Wiring
NOTE The Model 7707 is shipped with plastic connector covers installed on the D-shell connectors. Each
cover is secured to the connector by two screws. After removing a connector cover, retain it and
the screws for future use. Any unused D-shell connector must have the connector cover installed.
The Model 7707 is supplied with one 50-pin female IDC ribbon cable connector, and one 25-pin male IDC ribbon cable
connector. These ribbon cable connectors mate to the D-shell connectors of the switching module.
WARNING When using IDC ribbon cable connections on the DB-25 (analog inputs), DO NOT
exceed 42V on any analog input in the test system (including the front panel inputs of
the Model 27xx). For higher voltage applications (up to 300V), use wire rated for the
application and add supplementary insulation to the wire harness (
Figure 6 ).
The DB-50 connector is used for digital I/O connections. DO NOT exceed 40V on any
digital terminal in the test system.
There are two connector kits that have connectors that can be used with the Model 7707:
• Model 7790 ribbon cable adapter kit — Contains one female DB-50, one male DB-50 and one male DB-25 IDC
ribbon cable connectors. The female DB-50 and the male DB-25 mate to the D-shell connectors on the Model 7707.
• Model 7789 50/25-pin solder cup connector kit — Contains one male DB-50 and one male DB-25 solder cup
connectors. The male DB-25 mates to the 25-pin D-shell on the Model 7707.
IDC ribbon cable connections
WARNING When using IDC ribbon cable for analog inputs (DB-25), DO NOT exceed 42V on any
analog input (including front panel terminals). When using IDC ribbon cable for the
digital I/O (DB-50), DO NOT exceed 40V on any digital terminal.
Connect an appropriate length of 50-conductor IDC ribbon cable to a 50-pin female D-shell IDC connector, and connect an
appropriate length of 25-conductor IDC ribbon cable to a 25-pin male D-shell IDC connector.
Table 2 and Figure 3 provide
terminal identification for the 50-pin ribbon cable connections. Table 3 and Figure 4 provide terminal identification for the
25-pin ribbon cable connections.
The connectors of the prepared ribbon cable assemblies mate to the 50- and 25-pin D-shell connectors of the Model 7707
(
Figure 5 ). Make sure an unused D-shell connector has the connector cover installed.