An LVDT Signal Conditioner is an electronic device that converts the AC voltage signal from a Linear Variable Differential Transformer (LVDT) sensor into a standardized and usable output signal—such as 0–10 VDC, ±10 VDC, or 4–20 mA. It also provides the excitation voltage required to operate the LVDT.
Why Is a Signal Conditioner Necessary?
LVDTs are passive devices that rely on an external excitation source—typically a sinusoidal AC voltage. The signal conditioner performs several essential functions to ensure the sensor provides accurate and reliable position feedback:
Key Functions of an LVDT Signal Conditioner:
Provides Excitation Voltage
Supplies the AC voltage (typically 3 Vrms – from 2.5-10 kHz) needed to drive the LVDT coil.
Demodulates the AC Signal
LVDTs generate an AC signal that varies in amplitude with displacement. The signal conditioner converts this into a DC voltage or current signal that can be easily interpreted by PLCs, DAQ systems, and displays.
Amplifies and Filters the Signal
Enhances the LVDT signal and removes electrical noise or interference for stable, precise readings.
Offers Scalable Output Options
Allows users to choose from common output formats (0–10 VDC, ±10 VDC, 4–20 mA) depending on the control or monitoring system in use.
Enables Zero and Span Calibration
Most signal conditioners include adjustments or digital controls to fine-tune the sensor’s zero and full-scale outputs to match your application requirements.
When Should You Use an LVDT Signal Conditioner?
- You’re using an AC-operated LVDT that does not have built-in electronics.
- You need a standardized signal for input into a PLC, display, or DAQ system.
- Your application requires precision calibration of zero and span.
- You need to reduce noise and ensure signal stability over long cable runs.
Built-In vs. External Signal Conditioning
Some DC-operated LVDTs include built-in signal conditioning electronics. For AC-operated models, an external signal conditioner like the SC-200 or S2A is required for full functionality.
Need Help Choosing the Right Signal Conditioner?
Contact us today—our application engineers are ready to help you select the best solution for your LVDT-based system!