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Standard Exposed Junction Thermocouple for Controlled Conduction Errors in Measurement of Air or Exhaust Gas Temperature
- Aerospace Standard
Published May 03, 2018 by SAE International in United States
Downloadable datasets availableAnnotation ability available
The thermocouple design recommended herein is presented as one for which the correction to the observed emf, because of thermal conduction along the stem and wires, is within the limits presented in the accompanying figure. On referring to the figure, it is seen that no restriction is placed upon the diameter of the thermocouple or stem, and the longitudinal dimensions are expressed in terms of wire and stem diameters. The type of stem, such as packed ceramic stock, refractory insulating tubing, etc., also is left open to choice. Thus the sizes of wires and supporting stems may be varied over wide ranges to match particular requirements where conduction errors are to be limited or controlled.
ARP690 has been reaffirmed to comply with the SAE five-year review policy.
Data Sets - Support Documents
|[Unnamed Dataset 1]|
BackgroundEngine condition monitoring and rotorcraft HUMS(Health and Usage Monitoring Systems)can be used as a tool to track and restore engine performance, improve problem diagnosis, suggest solutions, promote better commercial and military aircraft operation, minimize in-flight failures, and reduce costs of engine maintenance. Because of these and other continuing objectives, the need for consolidated action by a group of experts to promote engine monitoring and rotorcraft conditio monitoring know-how and standards was identified. It was deemed appropriate by the SAE Propulsion Division to assign this task to a special committee designated as Committee E-32. The committee has existed for over 20 years and has 50 active members. Purpose / Charter Serves as a forum to gather, record, and publish expert information in the discipline of aircraft and helicopter engine condition monitoring and rotorcraft HUMS. The committee gathers and analyzes requirements for propulsion system monitoring for the various types of aircraft gas turbines and rotorcraft HUMS and develop standards and recommendations for the adoption of engine monitoring devices that affect the operation of gas turbine engines and rotorcraft. Objectives Identify potential engine and rotorcraft HUMS parameters suitable for sensing (pressure, temperature, etc.), and considerations involved in selecting parameters (potential problems, accuracy, cost, etc.). Analyze the various approaches to engine monitoring (e.g. airborne vibration monitoring systems and ground software interfaces, etc.) and establish criteria for the most cost-effective systems. Develop as appropriate, standards on engine and rotorcraft HUMS monitoring equipment and techniques, e.g. configuration of engine fittings for sensor connections, types of sensors, identification of signals which should be let to common diagnostic connectors, etc. Develop new requirements and uses for engine and rotorcraft HUS monitoring to promote cost-effective operation of aircraft. Sponsor technical conferences related to monitoring of air breathing engines and rotorcraft HUMS.
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