The document discusses data acquisition (DAQ) systems, emphasizing the roles of transducers, signal conditioning, and DAQ hardware in gathering and digitizing signals for analysis. It outlines the components of a basic DAQ system, the characteristics of analog signals, and the importance of selecting appropriate signal conditioning techniques to enhance measurement accuracy. Additionally, it covers the software application used to manipulate and present raw data obtained from the DAQ device.

1. BY – ABHISHEK SUR
SYSTEM ID- 2019595927
ROLL NO -190134001
SUBMITTED TO – SUMAN LATA DHAR

2.  DATA ACQUISITION
 ROLE OF TRANSDUCERS
 ANALOG SIGNALS
 SIGNAL CONDITIONING
 PARTS OF SIGNAL CONDITIONING
 COMPONENTS OF DAQ DEVICES

3.  Data acquisition involves gathering signals from a
measuring sources and then digitizing the signals
for storage, analysis and presentation on a PC.
 It may come in many different PC technology
forms to offer flexibility while choosing a
system.
 The main components for building a basic DAC
system are:-
 Transducers and Sensors
 Signals
 Signal conditioning
 DAQ hardware
 Driver and Application Software

4.  Now, Transducer is a device that converts a
physical phenomenon into measurable
electrical signal such as voltage or current
 It has the same agreement like that of
sensors in data acquisition system.
 There are specific transducers for many
different applications such as measuring
temparature, pressure and fluid flow.

5.  Phenomenon
 Temperature
 Light
 Sound
 Force &Pressure
 Acceleration
 Transducers
 Thermocouple, RTD
 Photo Sensor
 Microphone
 Strain gauge
 Accelerometer

6.  It is a type of signals that can exist at any
value with respect to time. Examples are
voltage, temperature, pressure, load.
 The three primary characteristics of an
analog signal are level, shape and frequency.

7.  LEVEL:- It gives us the vital information
about the measured analog signal. As when
we measure it the signal doesn't change
quickly with time. The accuracy is also
important.
 SHAPE:- Some signals are named after
specific shapes as square, sawtooth, triangle
etc. It is important because by analyzing the
shape we can further analyse the signal.

8.  FREQUENCY:- All analog signals can be
categorized by their frequencies. Unlike
level or shape you cannot directly measure
frequency. But it can be analysed in a
software through Fourier Transform.

9.  Sometimes transducers generate signals too
difficult to measure with a data acquisition
device.
 For that reason only signal conditioning is
used as for noisy environment, extreme high
or low signals it is used.
 It also maximizes the accuracy of the system
and allows sensor to operate properly and
assures safety.

10.  It is important to select the right hardware
for signal conditioning. It can be both
modular and integrated type:-
 Amplification
 Linearization
 Filtering
 Multiplexing

11.  Improves the accuracy in the digitized signal
and reduces the effects of the noise.
 Signals should be amplified close to the
source results into high SNR.
 For highest accuracy amplify the voltage
level to maximum input range of ADC.

12.  Most of the transducers have non-linear
response.
 LabVIEW can linearize the voltage levels
from transducers so that you can scale the
voltages to the measured phenomenon.
 Software based.

13.  It is to remove unwanted signals from the
signal of interest i.e. the signal which is to
be measured.
 Noise reduces the measurement accuracy.
 For DC signals Many SCXI-
Signal Conditioning Extension for Instrumenta
tion modules uses 4Hz and 10kHz low pass
filters to eliminate the noise before the
signals are digitized by DAQ device.

14.  Technique for measuring several signals with
a single device.
 The ADC samples one channel, switches to
next channel samples it, switches to next
channel and so on.
 Because same ADC samples many channels
instead of one, the effective sampling rate of
the individual channel is inversely to number
of channels sampled.

15.  Analog I/O
 Digital I/O
 MUX
 ADC
 DAC
 Counter
 RTSI (Real Time System Integration) Bus

16.  The DAQ device is an external and connects
to the computer through an exiting port such
as serial port or Ethernet port .
 The computer receives the raw data through
DAQ Device.
 The application which is written in the
software presents and manipulates the raw
data so that it can be understood.
 Software also controls the DAQ system by
commanding the DAQ device and manages
when and from which channel to acquire the
data.