Keithley 6517B Reference Manual

Section 3: Connections Model 6517B Electrometer Reference Manual
3-12 6517B-901-01 Rev. C / August 2015
Custom built test fixtures
Two examples of custom built test fixtures are shown in the following figures. The first is a dedicated
test fixture to source voltage and measure current to a single DUT (resistance measurements). The
second is a multi-purpose test fixture that can be used to make any Model 6517B measurement.
These two examples illustrate the basic techniques that should be applied when building a test
fixture. These same basic techniques should be used if you need to build a more complex test fixture
to accommodate your test measurement requirements.
The multipurpose test fixture assumes that ammeter input LO is connected to V-source LO inside the
Model 6517B. This LO-to-LO connection is controlled from the METER CONNECT selection in the
CONFIGURE V-SOURCE menu.
The following requirements, recommendations, and guidelines are provided in order to build a quality
test fixture that is safe to use. After building a test fixture you should clean it (see Handling and
cleaning test fixtures (on page 3-15)).
Test fixture chassis
 The chassis of the test fixture should be metal so that it can function as a shield for the DUT or
test circuit mounted inside. The chassis of the test fixture is connected to chassis ground of the
Model 6517B through the triaxial cable.
 The test box must have a lid that closes to prevent contact with live circuitry inside.
Safe operation requires that a safety interlock switch be used to place the V-source in
standby when the test fixture lid is open or ajar (see Interlock (on page 3-14)).
 The test fixture chassis must have a screw terminal that is used exclusively for connection to
safety earth ground.
To provide protection from shock hazards, the test fixture chassis must be properly
connected to safety earth ground. A grounding wire (#18 AWG or larger) must be attached
securely to the test fixture at a screw terminal designed for safety grounding. The other end
of the ground wire must be attached to a known safety earth ground.
Guard plate
A metal guard plate provides guarding or noise shielding for the DUT or test circuit. It also serves as a
mounting panel for the DUT or test circuits. The guard plate must be insulated with 1000 V spacing
from the chassis of the test fixture.

Keithley 6517B Specifications

General

Brand	Keithley
Model	6517B
Category	Measuring Instruments
Language	English