Description
NI PXI-4071 | 7½-Digit FlexDMM | 1.8 MS/s Isolated Digitizer
Key Technical Specifications
| Parameter | Specification |
|---|---|
| Manufacturer | National Instruments |
| Model | PXI-4071 |
| Instrument Type | PXI Digital Multimeter / FlexDMM |
| Resolution | 7½ digits |
| ADC Resolution | 26 bit |
| Maximum DC Voltage | ±1,000 V |
| Maximum AC Voltage | 700 V RMS |
| Maximum DC Current | ±3 A |
| Maximum AC Current | 3 A RMS |
| Resistance Range | 10 µΩ to 5 GΩ |
| DC Voltage Sensitivity | Down to 10 nV |
| DC Current Sensitivity | Down to 1 pA |
| Resistance Sensitivity | Down to 10 µΩ |
| Digitizer Sample Rate | Up to 1.8 MS/s |
| Digitizer Isolation | Isolated high-voltage mode |
| Measurement Functions | AC/DC V, AC/DC I, resistance, frequency/period, diode |
| PXI Platform | PXI |
| Replacement Listed by NI | PXIe-4081 |
NI describes the PXI-4071 as a 7½-digit, 1,000 V PXI DMM combining high-resolution DMM functions with an onboard 1.8 MS/s isolated digitizer. It supports AC/DC voltage and current, 2- or 4-wire resistance, frequency/period and diode measurements.
Archived NI technical material gives the major measurement ranges as 100 mV, 1 V, 10 V, 100 V and 1,000 V for DC voltage; current ranges extend from 1 µA through 3 A; resistance ranges extend from 100 Ω through 5 GΩ.
Product Introduction
The NI PXI-4071 is a high-resolution modular digital multimeter designed for PXI automated test systems. Its 7½-digit measurement capability is paired with an isolated digitizer mode, allowing the same PXI instrument to perform precision DMM measurements and capture high-voltage waveforms at sample rates up to 1.8 MS/s.
For production test and laboratory automation, the useful feature is the combination of precision measurement and waveform acquisition in one PXI slot. The instrument can cover very low-level signals as well as measurements approaching 1,000 V, but the applicable range, resolution, aperture time and accuracy must be considered together rather than treating the headline 7½-digit figure as a universal measurement accuracy.
PXI-4071
Application Scenarios & Field Pitfalls — Engineer’s Perspective
Engineering Pain Point
The PXI-4071 is often encountered in older automated test systems where the hardware, NI-DMM software and PXI chassis were designed as one validated measurement platform. Replacing it with a newer PXI Express instrument may preserve the headline specifications while still changing software behavior or application-level measurement handling.
Typical Applications
- Automated production test — precision voltage, current and resistance measurements.
- Electronic component characterization — low-level resistance and voltage measurements.
- Power electronics testing — high-voltage measurement and isolated waveform acquisition.
- PXI switching systems — DMM/switch scanning where measurement resolution and scan rate are jointly important. NI provides specific PXI-4071/DMM switch handshaking data for these applications.
Technical Pitfalls to Avoid
- Do not assume 7½ digits means 7½-digit accuracy.
Accuracy depends on the selected range, reading, aperture time, noise and other measurement conditions. NI’s accuracy methodology explicitly combines ppm-of-reading and ppm-of-range terms with noise considerations. - Do not treat PXIe-4081 as an electrically identical replacement.
NI lists PXIe-4081 as the suggested replacement, but documents behavioral differences between the PXI-407x and PXIe-408x families. Examples include averaging limits, calibration functions, waveform behavior and firmware-revision reporting. - Check the PXI chassis and software environment.
is a legacy PXI instrument. A replacement plan needs to consider the chassis slot, NI-DMM version, application software, switching architecture and existing calibration procedure. - Respect the high-voltage measurement category.
NI’s architecture documentation states that the can measure 1,000 VDC and 700 VAC RMS at CAT I levels. The 1,000 V figure should therefore not be interpreted as permission for arbitrary mains or installation-category measurements.
Related Products
- PXI-4070 — 6½-digit FlexDMM in the PXI family; lower resolution and measurement capability than .
- PXI-4072 — 6½-digit PXI FlexDMM with LCR measurement capability; better suited where capacitance/inductance measurements are required.
- PXI-4065 — 6½-digit PXI DMM for applications where the ‘s extended high-voltage and digitizer functions are not required.
- PXIe-4081 — NI’s listed successor for the , providing 7½-digit resolution, 1,000 V measurement and 1.8 MS/s isolated digitizer capability. It uses the PXI Express platform and should be validated at the application level before substitution.
- PXIe-4080 — PXI Express FlexDMM with different resolution and measurement ranges; not a direct specification-equivalent replacement for .
- PXIe-4082 — PXI Express FlexDMM with LCR capability; useful where impedance measurements are required.
Procurement Note
The is officially listed by NI as no longer available. NI’s product page identifies the PXIe-4081 as the suggested replacement, but the migration should not be approved solely from the specification sheet.
For a used or surplus , verify the exact model, serial number, calibration status, front connector condition, PXI chassis compatibility, NI-DMM software support, and measurement self-test results. For a replacement project, preserve the existing measurement ranges, switching topology, triggering scheme and calibration workflow before changing platforms.
One procurement detail is worth retaining: NI’s historical ordering information lists 778271-01 for the 7½-digit FlexDMM configuration. This can help when cross-checking older asset records against the model designation.
