Ohms Measurements
4-3
Ohms measurement methods
There are two methods to measure ohms: auto ohms and manual ohms. When using auto
ohms, the SourceMeter operates as a conventional constant current source ohmmeter. To use
this method, simply select an ohms measurement range (or use autorange), and take the reading
from the display. When using auto ohms, the default test current varies with the ohms range, as
summarized in Table 4-1.
NOTE
You cannot change the test current in the auto ohms mode. If you attempt to change
the source current in auto ohms, the SourceMeter will display an error message.
With the manual ohms mode you can select either source V or source I to make ohms mea-
surements, and the unit will automatically compute the resistance reading using the V/I mea-
surement method. After configuring the desired source and selecting a voltage or current
measuring range, select the
Ω
measurement method to display the calculated V/I ohms reading.
NOTE
To achieve optimum accuracy, the SourceMeter measures both V and I and uses
these values in ohms calculations (with source readback enabled). The measured
source value is more accurate than the programmed source value. For remote opera-
tion, the user specifies the functions to measure. See the resistance measurement
accuracy specifications in Appendix A for more information.
Table 4-1
Auto ohms default test currents
Auto ohms range*
Default test current
0
20
Ω
200
Ω
00
2k
Ω
0
20k
Ω
200k
Ω
00
2M
Ω
0
20M
Ω
200M
Ω
00
2G
Ω
0
20G
Ω
200G
Ω
00
2T
Ω
0
20T
Ω
100mA
0
10mA
00
1mA
100mA
0
10mA
00
1mA
00
1mA
100nA
0
10nA
00
1nA
100pA
0
10pA
00
1pA
*200M
Ω
maximum without PreAmp
Содержание 6430
Страница 26: ......
Страница 32: ......
Страница 78: ...2 14 Connections ...
Страница 98: ...3 20 Basic Source Measure Operation ...
Страница 138: ...5 30 Source Measure Concepts ...
Страница 156: ...6 18 Range Digits Speed and Filters ...
Страница 168: ...7 12 Relative and Math ...
Страница 176: ...8 8 Data Store ...
Страница 202: ...9 26 Sweep Operation ...
Страница 248: ...11 22 Limit Testing ...
Страница 310: ...16 6 SCPI Signal Oriented Measurement Commands ...
Страница 418: ...17 108 SCPI Command Reference ...
Страница 450: ...18 32 Performance Verification ...
Страница 477: ...A Specifications ...
Страница 489: ...B StatusandErrorMessages ...
Страница 498: ...B 10 Status and Error Messages ...
Страница 499: ...C DataFlow ...
Страница 503: ...D IEEE 488BusOverview ...
Страница 518: ...D 16 IEEE 488 Bus Overview ...
Страница 519: ...E IEEE 488andSCPI ConformanceInformation ...
Страница 523: ...F MeasurementConsiderations ...
Страница 539: ...G GPIB488 1Protocol ...
Страница 557: ......