National Instruments PXIe-4340 PXI Displacement Input Module

The PXIe-4340 (Part number: 785068-01) is a Displacement Input Module from National Instruments, which is well-suited for AC linear variable differential transformer (LVDT). This module can also be used for AC rotary variable differential transformer (RVDT) and is an excellent module for resolver and synchronous measurements. The NI PXIe-4340 offers four concurrently sampled AC LVDT input channels. The PXIe-4340 can operate at sample rates ranged up to 25.6kS/s per channel. Each channel in the NI PXIe-4340 has a 24-bit Analog to Digital Converter. All channels are capable of independently selectable excitation frequency and voltage.

The NI PXIe-4340 Displacement Input Module has a built-in remote sensor system, which automatically and constantly modifies for errors in excitation leads. Its use is most critical in applications that engage long wires and/or small gauge wires since these wires and/or small gauge wires have higher resistance. The remote sensor is additionally used to sense the excitation of synchronized channels and helps the NI PXIe 4340 measure accurate ratios across channels for sensors.

The NI PXIe-4340 module comes equipped with a Self-Calibration feature to adjust the radiometric gain and offset. Self-Calibration cancels out the drift of the analog motherboard. Additionally, self-calibration nulls the DC component of the excitation source and adjusts the amplitude against an internal reference. The NI PXIe-4340 Displacement Input Module does not support external adjustments, but can synchronize multiple channels at the same time. For this, channels must be configured on the same board. Channels also must have the same excitation frequency and amplitude. Two or more channels can be synchronized. It is used for resolvers or combinations of resolvers, LVDTs, RVDTs, and synchros.