A production digital multimeter should be selected from the measurement requirements, not only the displayed digit count. Check accuracy, range, integration time, triggering, switching and the performance required by the complete test sequence.
PXI-4071
The NI PXI-4071 is a 7½-digit PXI digital multimeter with an onboard isolated digitizer. NI documentation lists a digitizer rate of 1.8 MS/s. Digitizer sample rate and precision DMM reading rate are different operating characteristics; use the settings and limits in the specifications for the intended measurement.
PXIe-4081
The NI PXIe-4081 is a 7½-digit PXI Express digital multimeter with an onboard isolated digitizer. Its documented functions include voltage, current, resistance, frequency/period and diode testing. Verify the exact function and range in the specifications rather than assuming that all DMMs provide the same measurements.
Compare the complete measurement
- Accuracy: compare specifications at the intended range, temperature and calibration interval.
- Resolution: determine the resolution needed to distinguish the acceptance limits.
- Timing: include settling, integration, switching and software overhead when estimating test throughput.
- Connections: check the fixture, lead arrangement and switching hardware for the measurement.
- Platform: verify PXI or PXI Express slot compatibility, driver support and controller requirements.
Avoid misleading comparisons
A digit count is not an accuracy guarantee. A maximum digitizer rate is not the DMM reading rate at every resolution. Compare measurements under the same conditions and validate the proposed setup with a representative test sequence.
Manufacturer references
Browse PXI equipment or request an exact model. Confirm the configuration and measurement requirements before choosing an alternative.