What is Data Acquisition?
Data Acquisition is simply the gathering of information
about a system or process. It is a core tool to the
understanding, control and management of such systems or
processes. Parameter information such as temperature,
pressure or flow is gathered by sensors that convert the
information into electrical signals. Sometimes only one
sensor is needed, such as when recording local rainfall.
Sometimes hundreds or even thousands of sensors are needed,
such as when monitoring a complex industrial process. The
signals from the sensors are transferred by wire, optical
fibre or wireless link to an instrument which conditions,
amplifies, measures, scales, processes, displays and stores
the sensor signals. This is the Data Acquisition instrument.
In the past Data Acquisition equipment was largely
mechanical, using smoked drums or chart recorders. Later,
electrically powered chart recorders and magnetic tape
recorders were used. Today, powerful microprocessors and
computers perform Data Acquisition faster, more accurately,
more flexibly, with more sensors, more complex data
processing, and elaborate presentation of the final
What is a Data Logger?
A data logger is an electronic instrument which connects to
real world devices for the purpose of collecting
information. Data logger can be pictured as a black box
recorder in aeroplanes. These data loggers record mainly
voice and the plane stats data information.
Real world Devices could include the following:
• Temperature sensors
• Pressure sensors & strain gauges
• Flow and speed sensors
• Current loop transmitters
• Weather & hydrological sensors
• Laboratory analytical instruments
• And much more...
Why Collect Information?
To look back on past events and identify areas of interest
and most of all saving cost and time. These events could
assist in improving the following:
• Energy consumption
• Quality Assurance
Real Time Data Acquisition and Data Logging
Data Acquisition can be divided into two broad
classifications – real time data acquisition and data
logging. Real time data acquisition is when data acquired
from sensors is used either immediately or within a short
period of time, such as when controlling a process. Data
logging on the other hand is when data acquired from sensors
is stored for later use. In reality, there is a continuum of
devices between real time data acquisition and data logging
that share the attributes of both of these classifications.
Stand-Alone or PC based?
Dedicated data loggers have many inherent advantages over PC
based alternatives for the bulk of data acquisition tasks.
These include low power operation, standby power sources and
security of data in the event of power or communications
failure. Being specifically designed for the task, errors
due to influences such as poor noise immunity and unstable
operating systems are minimised. A dedicated data logger
supporting anything from thermocouples to strain gauge
sensors, will process and return data to a PC in real time.
Evolution in Data Acquisition
Data Acquisition technology continues to evolve, with high
speed data interfaces and networking forcing major change to
previous practices. Sensitive low level signals can now be
left in the field, with just the desired data being returned
to a remote computer for analysis. This is the function of a
dataTaker data logger or DAQ box, providing the
functionality and speed of a DAQ board, adding the
standalone capability to process, consolidate and log data
for later downloading. A series of data loggers
interconnected by a network allows data gathering closer to
sensors, for improved signal quality and reduced
A Simple Decision
So why choose data logger over other data acquisition
systems? Most data acquisition systems require installation
of a DA card in a PC and the connection and wiring of the
sensors. These systems work well in permanenty configured,
on-line applications but is difficult to implement and can
be costly. Data loggers significantly reduce the cost for
most logging applications and are much easier to implement,
and can be placed in areas that digital systems can not
reach. The simple alternative, dataTaker data loggers stand
alone solid state data loggers that operate anywhere,
independent of your computer. they store data in the format
you choose, compatible with your computer and your software
systems. dataTaker data loggers are flexible and any one of
our data loggers can easily be configured to gather data in
almost any environment you choose. There are dataTakers in
rain forests, down mines and in the upper atmosphere. In
cars, in boats and planes. on farms, in factories and
laboratories. dataTaker is truly universal.