Section 2: Measuring dc voltage with high accuracy
Model DMM7510 7½ Digit Multimeter Application Manual
2-6
DMM7510-904-01 Rev. D March 2021
Send the following commands for this example application:
-- Reset the instrument to the default settings.
reset()
-- Set the measure function to dc voltage.
dmm.measure.func = dmm.FUNC_DC_VOLTAGE
-- Set the measurement range to 10 V.
dmm.measure.range = 10
-- Set the number of power line cycles to 10.
dmm.measure.nplc = 10
-- Set the input impedance to auto so it selects 10 Gohm for the 10V range.
dmm.measure.inputimpedance = dmm.IMPEDANCE_AUTO
-- Enable autozero.
dmm.measure.autozero.enable = dmm.ON
-- Set the averaging filter type to repeating.
dmm.measure.filter.type = dmm.FILTER_REPEAT_AVG
-- Set filter count to 100.
dmm.measure.filter.count = 100
-- Enable the filter.
dmm.measure.filter.enable = dmm.ON
-- Read the voltage value.
print(dmm.measure.read())
Test results
The following table shows the tradeoff between accuracy and speed of measurements based on the
integration rate (NPLC), averaging filter, and autozero settings. The first row of data is from the setup
documented in this example. The other rows show the results if the integration rate, filter, and auto
zero settings are changed.
DC voltage
Measurement time (seconds)
Integration rate (NPLC) Filter
Auto zero
5.0700528516
50.702501353
10
ON
ON
5.0701004092
0.510109919
10
OFF
ON
5.0700203296
0.017853353
1
OFF
ON
5.070064163
0.019507031
1
OFF
OFF
