In much the same way as personal computers and the Internet have expanded our vocabulary, data acquisition also brings with it some new terminology. Due to the need to understand some of the terms used throughout this website, and in an effort to lessen the ‘glazed eye’ look that often accompanies someone’s entry into data acquisition, we have assembled a few of the commonly misunderstood terms and have attempted to provide a simple explanation of each.
Analog: This term simply refers to a sensor or signal having a large number of potential values. For instance a water temperature sensor is an analog sensor as the output varies continuously with the temperature. This type of sensor is also called a voltage output sensor. The analog channels of a data recorder are used to monitor these types of sensors.
Data Cartridge: A small rectangular device used to transfer data from the onboard data recorder to a PC without connecting a serial cable between the two. It is used just like you might use a floppy disc to transfer files from one PC to another.
Data Recorder: The onboard hardware device that collects and stores the information transmitted from the sensors. Sometimes referred to as a Data Logger or Computer.
Digital: This term refers to a sensor or signal having only two values. For instance a wide open throttle switch is either on or off. Digital channels, by counting or timing the transitions from off to on, can also be used to measure RPM. For instance, by monitoring the number of pulses from the ignition tach output, a data recorder can determine and monitor the engine RPM.
Download: The process of transferring the information stored in the data recorder to a device, such as a data cartridge, for the purpose of loading it into another piece of hardware, such as a desktop computer for analysis. Also see Upload.
EGT: Abbreviation for Exhaust Gas Temperature. EGT’s are commonly used as an indicator of whether a cylinder is running rich (cool) or lean (hot). Thermocouple probes in the exhaust headers are used to measure the EGT’s.
I/O Board: Abbreviation for Input/Output Board. A circuit board installed in your desktop computer to receive and transfer information. Commonly used to receive information uploaded from your data recorder via a data cartridge.
K or KB: Abbreviation for Kilobyte. Each sample of recorded data represents approximately two bytes. A kilobyte is 1024 bytes. It takes about 1 KB to display one page of double spaced text on your computer screen. Also see MB or Megabyte.
LED: Abbreviation for Light Emitting Diode. A common form of display such as used on wristwatches or gauges which use a digital readout rather than a needle.
MB: Abbreviation for Megabyte. A megabyte is one million bytes (technically correct 1,048,576), or one thousand (1,024) kilobytes. Most large novels could fit into a MB with room to spare. Your auto insurance policy disclaimer would not.
Memory: The capacity of a data recorder or PC to store information, usually expressed in Kilobytes or Megabytes. The length of the recording time is dependant upon how much memory is available. As the number of channels and/or sampling rates per second increase, the recording time is decreased. When purchasing a data recorder or computer get as much memory as you can afford.
Pro Analog Transducer Box: A rectangular box that houses up to four drop-in style transducers or signal conditioning modules. These allow a recorder to expand the number of analog channels it can support. Pro Analog Transducer boxes can be linked in series.
Sampling Rate: The number of times per second the data recorder logs a sample of the incoming information from a sensor. Many times the number of samples per second can be changed to suit your needs. A common myth is that faster sampling rates are better. This isn’t always true.
Software: The program that is installed on your PC’s hard drive from a CD or floppy disc that provides the instructions enabling your PC to display and process the information that is uploaded from your data recorder. All versions of the Racepak DataLink data analysis software are now Windows®-based programs.
Thermocouple: A probe inserted into a header, usually near the exit of the exhaust port. This is the ‘sensor’ for the exhaust gas temperatures. Thermocouples differ from other temperature probes due to the higher range of temperatures in which they must operate.
Transducer: A device that convert a physical property, such as a pressure or position, into a voltage signal that the data recorder can understand. Used on temperature, pressure, vacuum, or movement signals.
Upload: Refers to the process of transferring information to a piece of hardware of higher intelligence. In the case of motorsports this is often the transfer from a data recorder or a data cartridge into a laptop or desktop computer. Also see Download.
V-Net: An acronym for Vehicle Network, an exclusive Racepak system that allows the input or output of information from many sources over a single cable. V-Net greatly reduces the need for wiring and redundant sensors, while increasing the capabilities of the system. V-Net allows multiple components (gauges, data recorder, controller motors, lights, etc.) to share the signals being transmitted over the V-Net cable.
Windows®: is a registered trademark name of the Microsoft Corporation. The term has become generic when referring to the most common method of navigating your way around a computer program. It uses point-and-click on icons, rather than the need for written commands as used with the older DOS programs. Racepak’s DataLink software is a Windows-based program.