GHSA-750 TE Macro Sensors AC LVDT

Product Description

The GHSA-750-TE AC LVDT from Macro Sensors, distributed by Harold G. Schaevitz Industries (HGSI), is a rugged, spring-loaded linear position sensor designed for precision displacement measurement and dimensional gaging applications. Utilizing proven Linear Variable Differential Transformer (LVDT) technology, this sensor delivers highly accurate and repeatable position feedback using a non-contact electromagnetic measurement principle.

The GHSA-750 Series features a compact 3/4-inch diameter stainless steel housing with hermetically sealed coil windings. This construction makes it well suited for use in industrial environments where reliability, durability, and long-term measurement stability are critical. Electrical termination is available through sealed connectors, with the GHSA configuration using an axial connector and the GHSAR version utilizing a radial connector to reduce installed length.

Available in measurement ranges from ±0.050 inches to ±2.00 inches, the GHSA-750 Series provides flexibility for both high-resolution gaging and larger displacement measurement applications.

Spring-Loaded Design for Consistent Contact

The GHSA-750-TE incorporates a spring-loaded probe shaft that maintains continuous contact with the measured surface. The shaft is guided by a precision sleeve bearing and directly coupled to the movable core of the LVDT.

The internal spring applies a nominal force of approximately 6 to 20 ounces depending on the measurement range.

This spring-loaded configuration offers several important benefits:

• Consistent and repeatable contact with the measured surface

• Simplified mechanical installation without external linkages

• Reliable measurement performance in automated or manual systems

Because the probe is always extended by spring force, the sensor maintains stable engagement with the target, minimizing measurement variability due to inconsistent contact conditions.

AC LVDT Operating Principle

The GHSA-750-TE operates as an AC LVDT and requires an external signal conditioner to function. The sensor itself contains no internal electronics, relying instead on electromagnetic coupling to generate a position-dependent signal.

Typical operating characteristics include:

• Excitation voltage: 3.0 Vrms nominal

• Excitation frequency: 2.5 to 3.0 kHz

When AC excitation is applied to the primary winding, a magnetic field is generated that induces voltages in two secondary windings. These secondary windings are connected in opposition, producing a differential output signal that varies proportionally with the position of the movable core.

The external signal conditioner demodulates this AC signal and converts it into a usable DC output representing position and direction of movement.

Advantages of AC LVDT Architecture

The AC LVDT design provides several advantages, particularly in industrial applications:

• No internal electronics within the sensor body

• Greater tolerance to temperature extremes

• Ability to locate signal conditioning electronics remotely

• Flexibility in selecting output formats and system gain

Because the sensing element is entirely passive, the GHSA-750-TE is well suited for applications where environmental conditions may challenge sensors with integrated electronics.

Non-Contact Measurement Benefits

A key advantage of LVDT technology is its non-contact measurement principle. There is no electrical contact between moving and stationary components, eliminating wear-related failure modes.

This results in:

• Virtually unlimited mechanical life

• Stable output over millions of cycles

• Minimal maintenance requirements

• Consistent performance over time

Unlike potentiometers or other contact-based sensors, the GHSA-750-TE does not suffer from signal degradation due to mechanical wear.

Accuracy and Repeatability

The GHSA-750-TE is engineered for high-performance measurement applications:

• Linearity: ≤ ±0.25% of full range output

• Repeatability: < 0.01% of full range output

Repeatability is especially critical in dimensional gaging applications, where consistent readings are required for reliable quality control and process monitoring.

The use of a precision sleeve bearing combined with non-contact sensing ensures that measurement performance remains stable over time, even in high-cycle environments.

Hermetically Sealed Construction

The GHSA-750-TE features a fully stainless steel construction with hermetically sealed coil windings:

• Coil sealing to IEC IP68 standard

• Sealed housing and connector interface

This construction provides protection against:

• Moisture and humidity

• Dust and particulate contamination

• General industrial environmental exposure

The sealed design helps ensure long-term reliability and consistent measurement performance in demanding applications.

Wide Operating Temperature Range

The GHSA-750-TE is designed to operate across a broad temperature range:

• Operating temperature: –65°F to +220°F (–55°C to +105°C)

This wide operating range allows the sensor to be used in both controlled environments and more demanding industrial conditions.

Flexible Mounting and Compact Design

The GHSA-750-TE is designed for easy integration into a wide range of mechanical systems:

• 1/2-20 UNF threaded mounting

• Supplied hex nuts for secure installation

• Compact 3/4-inch diameter housing

The availability of both axial and radial connector configurations allows users to optimize installation based on space constraints and cable routing requirements.

Interchangeable Contact Tip

The sensor is supplied with an AGD standard No. 9 contact tip made from chrome-plated hardened tool steel.

• Fully interchangeable with other AGD-style tips

• Allows customization for different measurement surfaces and geometries

This flexibility makes the sensor adaptable to a wide variety of measurement applications.

Signal Conditioning and Output Options

Because the GHSA-750-TE is an AC LVDT, it requires an external signal conditioner to convert the AC output into a usable signal.

Typical output formats include:

• ±10 VDC for bidirectional measurement

• 0–10 VDC for unidirectional applications

• 4–20 mA current loop for industrial environments

The ability to select output format through the signal conditioner allows the sensor to be integrated into a wide range of control, monitoring, and data acquisition systems.

Typical Applications

The GHSA-750-TE is well suited for a variety of industrial applications, including:

• Industrial gaging systems

• Electronic dial indicators

• Fabricated metal product inspection

• Materials testing equipment

• Large shaft runout (TIR) measurement

Its combination of high repeatability, rugged construction, and flexible integration makes it ideal for both automated and manual measurement systems.

Summary

The GHSA-750-TE AC LVDT provides a reliable and accurate solution for industrial position measurement and dimensional gaging. With its spring-loaded design, hermetically sealed construction, wide operating temperature range, and non-contact sensing technology, it delivers consistent performance in applications where precision, durability, and long-term stability are essential.