By Macro Sesnsors
Resolution—
The smallest core position change that can be observed in the output of an LVDT is called resolution. Since an LVDT Linear Position Sensor operates on electromagnetic coupling principles in a friction-free structure, it can measure infinitesimally small changes in core position. This infinite resolution capability is limited only by the noise in an LVDT signal conditioner and the output display's resolution. In practice, the limitation on system resolution is the ability of the associated electronic equipment to sense the change in output of the LVDT Linear Position Transducer, which is called the signal-to-noise ratio of the system. With a properly designed LVDT measuring system, micro-inch resolution is not uncommon.
Repeatability—
Often, the single most important factor for any sensor is the ability to reproduce the same output for repeated trials of exactly the same input under constant operating and environmental conditions. This parameter, called repeatability, is the only irreducible and uncorrectable source of static error in any electromechanical measuring system. Repeatability error is the limiting factor in making any sensor-based measurement. A well-made LVDT Linear Position Sensor is so repeatable that overall transducer repeatability is affected only by the mechanical factors of the physical members or structures to which the LVDT’s core is attached and to which the LVDT’s coil is mounted.
Both repeatability and resolution contribute to overall measurement error, and are usually expressed as a percentage of full-scale output. These parameters apply equally well to both AC- and DC-operated LVDTs.