1. Data Logging and Control The Kingsway School

2. Data Logging Computers can be used to collect data. This is very useful for Scientists: Climatic data over a long period Temperature changes during a chemical process Radiation output from a star

3. Advantages of Data Logging It is automated and does not need to be supervised It is always accurate Data can be collected over long or short periods Data can be stored for later analysis Graphs can be plotted automatically

4. Sensors These are the input devices They convert physical quantities into electrical voltage Sensors have to be connected through an analogue to digital converter.

5. Types of Sensor Type of sensor What does it do? PressureUseful for detecting burglars as part of a burglar alarm system. Infra RedDetect body heat Thermistors (Heat) React to temperature in scientific experiments and ovens p H sensorsUseful in detecting acidity and alkilinity

6. Key Vocabulary Period of Logging The total time over which data is collected Logging Interval The time between each piece of data being collected. Eg Measuring an explosion requires intervals of thousandths of seconds and the period of logging may only be a fifth of a second. But measuring temperature may be done over a year with intervals of an hour.

7. Control in a Greenhouse Computer Sensors Window