The D/L modules are NAI’s latest generation LVDT/RVDT Simulation Modules. These programmable, isolated output modules used on our multifunction embedded boards and SBCs are unique, solid-state designs that operate between 47 Hz and 20 kHz.
Linear Variable Differential Transformer (LVDT) and Rotary Variable Differential Transformer (RVDT) are transformer-type voltage/current transducers that convert a linear/rotary movement of a core/shaft to a multi-wire differential AC electrical signal. Both deliver signals linearly proportional to the position of a shaft (magnetic induction core). An LVDT/RVDT simulator is used to convert digital positional commands to corresponding AC signals.
A wide variety of D/L modules cover the range of excitation voltages/frequency, include extensive field-parameter programmability, and provide a full operating envelope choice for simulating virtually any type of LVDT or RVDT. By eliminating the need for external transformers and operating with lower AC reference frequencies, these solid-state designs offer huge space savings.
There are three types of D/L modules:
These high-density modules have a lower power output drive (0.5 VA per channel, max.). The lower power output drive is ideal for driving solid-state input instruments, gauges (most LVDT/RVDT measurement circuits are high input impedance, as "real" LVDTs/RVDTs do not supply a large amount of current).
The 2-channel modules have a standard (1.5 VA per channel, max.).
The single-channel modules have a high-power output drive capability (3 VA per channel, max.).
All LVDT/RVDT simulation modules feature a wrap-around self-test capability and most platforms support an optional programmable AC excitation supply. In addition to state-of-the-art technologies and design algorithms, the modules include many other useful application features such as excitation loss detection, and excitation voltage and frequency measurement. They can be programmed (and re-programmed) in the field for any excitation and simulating signal voltage between 2 - 28 Vrms or 28 - 90 Vrms full scale range. Individual excitation inputs are supplied for each A and B output pair.
All LVDT/RVDT simulation modules feature a wrap-around self-test capability and most platforms support an optional programmable AC excitation supply. Utilizing state-of-the-art technologies and design algorithms, many useful application features such as excitation voltage and frequency measurement, excitation loss detection and many others are “built-in.” They can be programmed (and re-programmed) in the field for any excitation and simulating signal voltage between 2 and 28 Vrms or 28-90 Vrms full scale range.