Keithley 6517A, Руководство пользователя

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Front Panel Operation
2-16
Guard plate
A metal guard plate will provide guarding or noise shielding
for the DUT or test circuit. It will also serve as a mounting
panel for DUT or test circuits. The guard plate must be insu-
lated with 1000V spacing from the chassis of the test fixture.
Connectors, terminals and internal wiring
Figures 2-16 and 2-17 show the types of connectors needed
to use the test fixtures with the Model 6517A. All connectors,
except the triax connector, must be insulated from the chassis
of the test fixture. The outer shell of the triax connector must
be referenced to chassis ground. Thus, DO NOT insulate the
outer shell of the triax connector from the metal chassis of
the test fixture.
DUT and test circuits are to be mounted on the guard plate
using insulated terminals. To minimize leakage, select termi-
nals that use virgin Teflon insulators.
Inside the chassis of the test fixture, you may use coaxial ca-
ble to extend guard from the triax connector to the DUT. The
shield (guard) of the cable should extend as far as possible to
the DUT.
Interlock
When a normally-open, SPST momentary switch is properly
implemented as a safety interlock, the V-Source will go into
standby whenever the test fixture lid is open or ajar. See para-
graph 2.9.4 for more information on the interlock feature of
the Model 6517A.
NOTE
An "Interlock Violation Error" message
will be displayed when the interlock is
open.
The switch must be mounted inside the test box such that it
will be closed when the lid of the test fixture is closed. Open-
ing the lid must cause the interlock switch to open. There
must never be enough clearance to allow finger access inside
the box while the switch is closed. The interlock must be de-
signed so that it cannot be defeated.
By using an appropriate bulkhead connector on the test fix-
ture, the Keithley Model 6517-ILC-3 Interlock cable can be
used to connect the interlock switch to the Model 6517A (see
Figure 2-18A). The connector needed is shown in Figure 2-
18C. Figure 2-18B shows the dimensions of the hole that
must be cut into the test fixture chassis to mount the connec-
tor. Figure 2-18D shows how to wire the connector to the test
fixture interlock switch.
As an alternative, you can remove one of the plugs from the
Model 6517-ILC-3 and hard wire the interlock cable directly
to the interlock switch of the test fixture as shown in Figure
2-19.
To 6517A
Interlock
To 6517A
V Source
Out HI
To 6517A
Input
Interlock Switch
Open Lid = Open Switch
Insulated
Terminal
Post (2)
Screw Terminal for
Safety Earth Ground
Warning : Test fixture must
be connected to safety earth
ground using #18 AWG wire
or larger.
Interlock Connector
Banana Jack
3-Lug Female Triax Connector
A
B
C
Guard Plate
1
2
3
A
B
C
DUT
4
Figure 2-16
Test fixture to source voltage, measure current (resistance measurements)