Front Panel Operation
2-41
USE-ALL-RANGES: With this selection, all ohms ranges
(except the 2T
Ω
, 20T
Ω
and 200T
Ω
ranges) are used in the
autoranging search process.
SET-LIMITS: This selection allows you to specify minimum
and maximum ranges in the autoranging search process:
• MIN-AUTO — Use to select the lowest range that you
want the instrument to autorange to.
• MAX-AUTO — Use to select the highest range that you
want the instrument to autorange to.
DAMP
High capacitance seen at the input will increase reading
noise. This capacitance can be attributed to a long input cable
or to the capacitance of the source, or a combination of both.
Enabling damping will reduce this type of noise. However,
damping will also slow down the response of the measure-
ment.
Don't confuse damping with filtering. Damping is used to re-
duce noise caused by input capacitance, while filtering is
used to reduce noise caused by a noisy input signal.
ON: Enable current damping
OFF: Disable current damping
MEAS-TYPE
The MEAS-TYPE option is used to select and configure the
measurement type for the ohms function.
RESISTANCE: Use this menu item to configure the ohms
function to make normal resistance measurements.
RESISTIVITY: Use this menu item to configure the ohms
function to make surface or volume resistivity measure-
ments:
NOTE
If the Model 6517A is already configured
to use the Model 8009 Resistivity Test
Fixture (see FIXTURE-MODEL) then the
interlock cable MUST be connected to
that test fixture. Measurement type (sur-
face or volume) is automatically selected
by the switch position on the test fixture.
Attempts to change measurement type
from the menu will be ignored. If the inter-
lock cable is not connected, then the set-
tings for volume or surface will not work
properly, and you will not be able to
change measurement type from the menu.
SURFACE — Select this option to make surface resistivity
measurements. After the option is selected, the following
menu items are used to configure the resistivity measure-
ment:
MODEL-8009: Use this option if you are using the Model
8009 Resistivity Test Fixture. This option automatically sets
the parameters for the surface resistivity calculation (see
paragraph 2.7.2) since the electrode dimensions are known.
USER: Use this option if using another manufacturer’s test
fixture or a custom-built test fixture. After selecting this op-
tion you will be prompted to enter the value for K
s
. Para-
graph 2.7.2 explains how to calculate K
s
.
VOLUME — Select this option to make volume resistivity
measurements. After the option is selected, the following
menu items are used to configure the resistivity measure-
ment:
THICKNESS: Use to specify (in millimeters) the thickness
of the sample.
FIXTURE-MODEL: Use this menu item to select the test
fixture that you are going to use:
• MODEL-8009 — Select this option if using the Model
8009 Resistivity Test Fixture. This option automatically
sets the parameters for the volume resistivity calcula-
tion (see paragraph 2.7.2) since the electrode dimen-
sions are known.
• USER — Use this option if using another manufactur-
er’s test fixture, or a custom-built test fixture. This op-
tion is also used for the Model 8009 test fixture if using
an effective area coefficient less than one (B < 1). After
selecting this option you will be prompted to enter the
value for K
v
. Paragraph 2.7.2 explains how to calculate
K
v
.
VSOURCE
The VSOURCE menu item is used to select either AUTO V-
Source or MANUAL V-source:
• MANUAL — Select this option if you wish to manually
set the V-Source range and level for the ohms function.
• AUTO — Select this option if you wish the Model
6517A to automatically select the optimum V-Source
range and level for the ohms function; 40.000V for the
2M
Ω
through 200G
Ω
ranges, and 400.00V for the 2T
Ω
through 200T
Ω
ranges. With AUTO V-Source selected,
you will not be able to manually set the V-Source range
or level while in the ohms function.
