Fluke 189 - Manual (Page 45)

Making Measurements
Using Conductance for High Resistance Tests
3
3-9
Continuity testing provides you with both a visual
indication of the state encountered (usually near 0
resistance for a short or OL for an open) and an audible
beep when the input is low.
In continuity, a short means a measured value less than
5% of full scale. You can raise this threshold by manually
selecting a higher range.
You can select whether the beeper comes on for open or
short conditions, as follows:
•
Press
[
to enable the beeper for opens.
•
Press ] to enable the beeper for shorts.
The Hz ( N ) and FAST MN MX ( O M )
functions are not available when continuity is selected. All
other pushbutton functions are available. The blue key
cycles among resistance, continuity, and conductance.
Using Conductance for High Resistance
Tests
Conductance, the inverse of resistance, is the ability of a
circuit to pass current. High values of conductance
correspond to low values of resistance.
The unit of conductance is the Siemens (S). The meter’s
50 nS range measures conductance in nanosiemens
(1 nS = 0.000000001 Siemens). Because such small
amounts of conductance correspond to extremely high
resistance, the nS range lets you determine the resistance
of components up to 100,000 M
Ω
, or 100,000,000,000
Ω
(1 nS = 1,000 M
Ω
).
To measure conductance, set up the meter as shown in
Figure 3-7; then press the blue key until the nS indicator
appears on the display.
With conductance measurements, the following
pushbutton operations cannot be used:
•
Frequency ( N )
•
FAST MN MX ( O M )
•
Manual ranging (
R
)