Thermocouples & Thermoresistances - ROTFIL - #1

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Thermocouples & Thermoresistances Symbol E G U Thermocouples MgO Insulation Thermocouples MgO-insulated thermocouples are made of two or more wires, inside a highly compacted MgO insulation powder. Various materials can be used for the external metallic body, according to the specific working conditions. MgOinsulated thermocouples are manufactured and tested according to ASTM E608, and comply to ANSI MC 96.1 or DIN 43710 standards. The thermocouple leads are inserted in ceramic insulators, that are housed, together with alumina powder, in protective bodies to ANSI/DIN specifications. The main application of these temperature gauges is when no vibrations, mechanical stresses or pressure loads are applied. Conventional Insulation Thermocouples Thermocouple Junction Types There are 3 types of wire junction in thermocouples. The type shall be chosen according to the characteristics of the application. The below comparison chart might help. E G U Type Response Time In Corrosive Environments With Vibrations Other Features EXPOSED JUNCTION Very short Not good Not good Shall be handled carefully to avoid damage to the junction. Very good Very good whenever parasitic emf could affect accurate measurement. GROUNDED JUNCTION Short Good Not good Temperature probes are basically two wires with particular thermoelectric features, electrically insulated from each other and from the external protection body. This type of temperature gauge is very reliable and quickly responding. Depending on their various construction features, they are individually optimized to fully fit in a great number of industrial applications. The most significant input data needed to design a temperature probe are operative temperature range and working conditions. Very good with high pressures (up to 3500 Kg/cm², or 350 MPa). UNGROUNDED JUNCTION Longer Very good Thermocouples, PDF-TCR-011-E-1/10