Operating Considerations - Keithley 6487 Reference Manual

Model 6487 Reference Manual
Figure 3-8
A-V ohms reading recall sequence
RDG NO.
RDG NO.
RDG NO.
RDG NO.
RDG NO.
RDG NO.
RDG NO.
RANGE
RDG NO.
RANGE RDG NO.
RDG NO.
STD STD DEV DEV
AVERAGE AVERAGE
PK-PK PK-PK
MIN AT
MAX AT
Buffer Statistics
*Maximum current will result in minimum ohms and vice-versa.
The MIN value applies to the minimum amps (maximum ohms) reading.
The MAX value applies to the maximum amps (minimum ohms) reading.

Operating considerations

Range
Auto range cannot be used with A-V ohms. Auto range will be automatically disabled
when arming A-V ohms from the front panel. Over the GPIB, however, sending the
CURR:OHMS:AVOL:ARM command with auto range on will result in error +852 "No
A-V ohms with Autorange". Also, only the following ranges can be used: 20nA, 2µA,
200µA, and 20mA. If on any other range, the unit will uprange to the closest allowed range.
Filtering
The median and average filters are not used in the A-V ohms mode. Once the A-V ohms
process is complete, the state of the filters will be restored.
Rate and autozero
During A-V ohms, integration rates are restricted to either 0.02 PLC, 0.1 PLC, 1 PLC, 6 PLC,
or 60 PLC. Autozero is turned off but restored after completion if it was previously on. If the
integration rate is set to any other value, it will be set to the closest of these settings. However,
the original integration rate will not be restored at the conclusion of the A-V ohms cycle.
Integration times of 0.02 PLC and 0.1 PLC will automatically cause the display to be dis-
abled during the A-V ohms run. After the desired number of cycles has completed (or an
OHMS:AVOL:ABORt command is received), the display will be restored.
10 Reading Value (Amps)
9 Reading Value (Amps)
8 Reading Value (Amps)
7 Reading Value (Amps)
6 Reading Value (Amps)
5 Reading Value (Amps)
4 Reading Value (Amps)
3 Reading Value (Amps)
2 Reading Value (Amps)
1 Reading Value (Amps) g p
Standard Deviation Value Standard Deviation Value
Average Value Average Value
Peak to Peak Value Peak to Peak Value
XX Minimum Value (Amps)*
XX Maximum Value (Amps)*
Amps
Measurements and Sourcing Voltage
Reading Value (Ohms)
Reading Value (Ohms)
Reading Value (Ohms)
Reading Value (Ohms)
Reading Value (Ohms)
Reading Value (Ohms)
Reading Value (Ohms)
Reading Value (Ohms)
Reading Value (Ohms)
Reading Value (Ohms)
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Minimum Value (Ohms)*
Maximum Value (Ohms)*
Ohms Voltage Source
3-25
Vsource
Timestamp
Timestamp
Vsource
Timestamp
Vsource
Timestamp
Vsource
Timestamp
Vsource
Timestamp
Vsource
Timestamp
Vsource
Timestamp
Vsource
Timestamp
Vsource
Timestamp
Vsource
Timestamp
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Vsource Timestamp
Timestamp
Vsource
Buffer
Timestamps