Keithley System SourceMeter 2601B, Справочное руководство

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Section 7: TSP command reference Series 2600B System SourceMeter® Instrument Reference Manual
7-210 2600BS-901-01 Rev. B / May 2013
smuX.measure.rangeY
This attribute contains the positive full-scale value of the measurement range for voltage or current.
Type TSP-Link accessible Affected by Where saved Default value
Attribute (RW) Yes Instrument reset
SMU reset
Recall setup Saved setup Voltage:
Models 2601B/2602B/2604B:
100e-3 (100 mV)
Models 2611B/2612B/2614B/2634B/
2635B/2636B: 200e-3 (200 mV)
Current:
100e-3 (100 mA)
Usage
rangeValue = smu X .measure.range Y
smu X .measure.range Y = rangeValue
rangeValue
Set to the maximum expected voltage or current to be measured
X Source-measure unit (SMU) channel (for example,
smua.measure.rangev
applies to SMU channel A)
Y SMU measurement function (
v
= voltage,
i
= current)
Details
Reading this attribute returns the positive full-scale value of the measurement range that the SMU is currently
using. Assigning a value to this attribute sets the SMU on a fixed range large enough to measure the assigned
value. The instrument will select the best range for measuring a value of
rangeValue
.
This attribute is primarily intended to eliminate the time that is required by the automatic range selection
performed by a measuring instrument. Because selecting a fixed range prevents autoranging, an overrange
condition can occur. For example, measuring 10.0 V on the Model 2601B/2602B/2604B 6 V range or measuring
5.0 V on the Model 2611B/2612B/2614B 2 V range causes an overrange. The value 9.37 is returned
when this occurs.
If the source function is the same as the measurement function (for example, sourcing voltage and measuring
voltage), the measurement range is locked to be the same as the source range. However, the setting for the
measure range is retained. If the source function is changed (for example, from sourcing voltage to sourcing
current), the retained measurement range is used.
Model 2601B/2602B/2604B example: Assume the source function is voltage. The source range is 1 V and you
set the measure range for 6 V. Since the source range is 1 V, the SMU performs voltage measurements on the 1
V range. If you now change the source function to current, voltage measurements is performed on the 6 V range.
Explicitly setting a measure range will disable measure autoranging for that function. Autoranging is controlled
separately for each source and measurement function: source voltage, source current, measure voltage and
measure current. Autoranging is enabled for all four by default.
Changing the range while the output is off does not update the hardware settings, but querying returns the range
setting that will be used once the output is turned on. Setting a range while the output is on takes effect
immediately.
With measure autoranging enabled, the range is changed only when a measurement is taken. Querying the
range after a measurement returns the range selected for that measurement.
Example
smua.measure.rangev = 0.5 Selects the 1 V measurement range for SMU channel A.