Signal Conditioning – Essential Guide

We’re dealing with signals in our day today lives. During the development of electronics and science we could find out that the analog signals can be transmitted and stored as binary numbers. And this type of signals were named as digital signals.

Analog signals are the signals that exists in our natural environment. And it’s a continues signal that depends on the change in amplitude of the voltage or current. For example, an analog microphone transmits it signal by converting sound in to varying voltages on a wire. But the problem with analog signals is, when it transfer, it degrades.

But when we convert the analog signals to digital, it’s easy to transfer, store, amplify and scale without a degrade. To covert analog to digital and digital to analog, we use signal conditioning.

Signal conditioning is the manipulation of one type of signal in order to convert it to an another type. The purpose of signal conditioning is to bring a signal from the sensing element up to the format that is compatible with the load device

Analog to digital and digital to analog conversion are the primary functions of signal conditioning. However, any type of signal manipulation is called signal conditioning.

Signal Conditioner

Signal conditioner is a type of device that can manipulate a signal in to an another type of signal.   The primary function of a signal conditioner is to covert Analog Signals to Digital (ADC) and the Digital to Analog Conversion (DAC).

Most of the industrial signals are noisy, and also have a low amplitude. So, it’s difficult to get accurate measurements. By using the help of signal conditioners, we have the ability to clean the signals to some extent.

Different Types of Signal Conditioners

Temperature Signal Conditioner

Temperature signal conditioners have specially designed to use with temperature sensors. It receives the varying voltages as AC or DC from different type of temperature sensors such as Thermocouples, Resistance Temperature Detectors (RTD) and Thermistors.

And it provides the output signal as a digital signal.

LVDT Signal Conditioner (Linear Variable Differential Transformers)

LVDT conditioners have specially designed to use with are LVDT displacement transducers. And it is used in many applications such as materials testing, turbine control systems, steam valves, and gaging.

For example, let’s take a LVDT Datasheet

VeriFast LVDT Electrode 
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IMaLl 
Micro 12 mm, 5•pin, plug connector 
Signal Conditioner 
Micro 12 mm, Spin, shielded female cord 
(Female)

This is a image taken from VeriFast LVDT Signal Conditioner Data Sheet. As you can see, LVDT transducer. To setup the system, first we connect the Male plug connector (micro 12 mm, 5 pin) to the female connector. And then the we connect the end of the cable to the signal conditioner.

After that, you can get a 0-10 VDC output from the signal conditioner.

Torque Signal Conditioner

Torque signal conditioners have specially designed to use with torque transducers. It’s used to detect torsional deformation of a metal shaft by using a strain gage. When the torque is applied to the transducer, the input voltage of the conditioner changes.

Pressure Signal Conditioner

Pressure signal conditioners are specially designed to use with pressure transducers which are use with strain and stress measurements.

Pressure Signal Conditioners used in machineries where the internal pressure need to be measured.

Strain Gauge Signal Conditioner

Strain gauge signal conditioners are specially designed to use with strain gauge transducers. It converts the mechanical elongation caused by change in applied load, into a digital signal.

It’s using for testing vehicles, structural and constructional components.

Symbols Used in the Connection Diagrams

Resources

  1. LVDT Signal Conditioning
  2. https://www.cntrline.com/uploads/documents/Signal%20Conditioner%20Data%20Sheet-FDP-VFA-LVD-DS-EL-1_8-0220.pdf
  3. https://stevenengineering.com/Tech_Support/PDFs/32_SIGNAL-CONDITIONING.pdf