Transducer Electronic Data Sheets TEDS

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Transducer Electronic Data Sheets (TEDS)

• Lee H. Eccles
• Boeing Commercial Airplanes
• P. O. Box 3707, M/C 14-ME
• Seattle, WA 98124-2207
• Lee.h.eccles_at_boeing.com
• 206-655-2824

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Transducer Electronic Data Sheets

• What are they?
• A tool to enable true plug and play operation!
• A method of supplying information to the user!
• Why use them?
• To have plug and play operation!
• To always be able to find the data sheet!

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Paper Data Sheets

• A paper data sheet contains
• Information to be used to select the appropriate
  device for the task.
• Information to be used to set up the system to be
  able to use the device.
• There is no universally accepted format or
  required content.

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Electronic Data Sheets

• Electronic data sheets contains
• Information to be used to select the appropriate
  device for the task.
• Information to be used to set up the system to be
  able to use the device.
• User information is free format.
• System information is in a fixed format.

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Information for the User

• The information should be text based.
• Graphical information is desirable.
• There is different information required for each
  different device.
• No fixed format is practical.
• Multiple languages must be supported.

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Information for the Users System

• Machine readable
• Many users will never try to read the
  information.
• Others will.
• The content must be defined in detail.
• It is this information that enables true plug and
  play operation.

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Three Standards, Four Interfaces
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Physical Variables

• What is measured or controlled?
• Transducer type (i.e. pressure, temperature,
  flow, etc.)
• Range of measurement
• Unique features
• Etc.
• Information can be text based.
• The system does not need this information to
  operate.

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Interface Information

• The standard defines the interface
• The TEDS provide the operational details
• Data format
• Interface and data timing
• Etc.

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TEDS Definition

• IEEE Std 1451.2-1997 provided the first standard
  to define TEDS.
• IEEE p1451.3 TEDS are patterned after IEEE Std
  1451.2
• Different interface
• Details are different
• IEEE p1451.4 TEDS are totally different
• Analog interface
• Different requirements

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Machine Readable TEDS

• IEEE Std 1451.2
• Meta-TEDS
• Channel TEDS
• Calibration TEDS

• IEEE p1451.3
• Meta-TEDS
• Channel TEDS
• Calibration TEDS
• Transfer Function TEDS
• Frequency Response TEDS
• Commissioning TEDS

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Human Readable TEDS

• IEEE Std 1451.2
• Meta Identification TEDS
• Channel Identification TEDS
• Calibration Identification TEDS

• IEEE p1451.3
• Definitions taken from IEEE Std 1451.2
• XML Based
• XML allows the manufacturer to change the
  contents
• Commands TEDS
• Contains the setup commands

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TEDS Size Comparisons
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IEEE p1451.4 TEDS

• Compact TEDS
• The TEDS are 256 Bits in size Maximum
• TEDS are different for each application
• A template is required to describe the TEDS to
  the system

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Virtual TEDS

• Some applications need to separate the TEDS from
  the transducer module.
• Most consider this an undesirable feature
• Required for some applications
• IEEE p1451.3 allows TEDS to be stored external to
  the transducer module.
• These are called Virtual TEDS
• They have the same format as the embedded TEDS