Model 6487 Reference Manual
Measurements and Sourcing Voltage
3-25
Figure 3-8
A-V ohms reading recall sequence
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.
RANGE
RANGE
RDG
NO.
10
Reading Value (Amps)
Reading Value (Ohms)
Vsource
RDG
NO.
9
Reading Value (Amps)
Reading Value (Ohms)
Vsource
RDG
NO.
8
Reading Value (Amps)
Reading Value (Ohms)
Vsource
RDG
NO.
7
Reading Value (Amps)
Reading Value (Ohms)
Vsource
RDG
NO.
6
Reading Value (Amps)
Reading Value (Ohms)
Vsource
RDG
NO.
5
Reading Value (Amps)
Reading Value (Ohms)
Vsource
RDG
NO.
4
Reading Value (Amps)
Reading Value (Ohms)
Vsource
RDG
NO.
3
Reading Value (Amps)
Reading Value (Ohms)
Vsource
RDG
NO.
2
Reading Value (Amps)
Reading Value (Ohms)
Vsource
RDG
NO.
1
Reading Value (Amps)
Reading Value (Ohms)
Vsource
STD
DEV
Standard Deviation Value
----------
----------
AVERAGE
Average Value
----------
----------
PK-PK
Peak to Peak Value
----------
----------
MIN
AT
XX
Minimum Value (Amps)*
Minimum Value (Ohms)*
Vsource
MAX
AT
XX
Maximum Value (Amps)*
Maximum Value (Ohms)*
Vsource
g
p
STD
DEV
Standard Deviation Value
AVERAGE
Average Value
PK-PK
Peak to Peak Value
Buffer Statistics
Buffer
Timestamps
Timestamp
Timestamp
Timestamp
Timestamp
Timestamp
Timestamp
Timestamp
Timestamp
Timestamp
Timestamp
Timestamp
----------
----------
----------
Timestamp
Timestamp
▲
▲
▲
▲
▲
▲
Voltage Source
▲
▲
*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.
Amps
Ohms
