These models may be used with any series-opposed 5-, 6-, or 7-wire LVDT sensors or 3-wire variable reluctance transducers that can be operated with a 3-kHz frequency. Optional remote sensing is available for long cables.

The Model 3130 LVDT Conditioner is the basic “Form 1” instrument.

The Model 3230 LVDT Conditioner / Indicator is the basic “Form 2” instrument, providing vivid front-panel digital indication of measured values. The available scales allow ready calibration over virtually any measurement range, with a wide choice of engineering units. Instrument sensitivity and resolution allow precision to a fraction of a microinch, if required.

The Model 3330 LVDT Conditioner / Indicator / Controller is the basic “Form 3” instrument, and includes HI/LO limit detection. This feature is useful in a wide variety of “GO NO-GO” gaging applications (see Using a 3000 “Form 3” Conditioner / Indicator / Controller for “GO NO-GO” Dimensional Gaging of Parts).

Working on the synchronous carrier-demodulator principle, all three instruments supply amplitude-regulated 3-kHz AC excitation to the transducer. Two standard 5-V outputs are produced. Each output is precisely proportional to LVDT core displacement over the full ± range of the sensor. Sensitivity is widely adjustable, allowing full-scale output for input displacements as small as ±0.001 inch (±0.0254 mm).

A unique phase-control circuit automatically and continuously adapts the instrument to any signal phase shift occurring in the transducer or cable. This simplifies setup procedures, and ensures optimum sensitivity and linearity for each type of LVDT sensor employed.

Span adjustment is accomplished through 12-turn Coarse and Fine front-panel controls plus 5 internal range multiplier switches. Nominal maximum sensitivity is 10 mV (in-phase component) for full-scale input.

3000 Series options applying to these instruments include

Analog Peak Capture (Models 3230 and 3330)
4-20 mA Current Output (all models)
0-10 VDC Dual Galvanic Isolated Output (Models 3130 and 3230)
Internal Relays, Electromechanical and Solid-State (Model 3330)
12 VDC Battery-Powered Operation (all models)
Nominal 230 VAC Operation (all models)