5) Termocoppie in commercio.

 

5.1) Normative internazionali.

 

Visto il loro largo utilizzo, le termocoppie sono standardizzate secondo normative internazionali.

I vari tipi di termocoppia seguono la stessa denominazione letterale per tutte le normative.

Queste sono

 

Tipo T        :       rame/costantana

Tipo J :     ferro/costantana

Tipo E :     Chromel®/costantana

Tipo K :     Chromel®/Alumel®

Tipo N :     Nicrosil/Nisil

Tipo R :     platino 13% rodio/platino

Tipo S  :    platino 10% rodio/platino

Tipo B  :    platino 30% rodio/platino

 

I cavetti sono contrassegnati con colori a seconda dalla normativa seguita.

Qui di seguito riporto le principali normative con i rispettivi colori.

 

United States ASTM e ANSI:

 

 

 

 

British BS1843: 1952:

 

 

 

British BS4937: Part 30: 1993:

 

 

French NFE:

 

 

 

German DIN:

 

 

 

Fig. 5.1: colori delle termocoppie in commercio

 secondo le varie normative internazionali.

 

 

Accanto alle normative sulle colorazioni, ci sono normative sulle tolleranze e sul range di temperatura di utilizzo.Queste sono elencate nella tabella seguente.

Si nota come gli intervalli di utilizzo e la precisione richiesta sulla singola termocoppia vari da normativa a normativa.

Sta comunque alla singola ditta rivenditrice di termocoppie fornire delucidazioni sulla normativa a cui fa riferimento nelle specifiche dei prodotti.

 

 

Tab. 5.1: tolleranze e intervalli di utilizzo secondo le varie normative.

Per quanto riguarda le tensioni termoelettriche sviluppate, vengono indicate allo stesso modo le normative a cui fare riferimento.

Le tabelle trovate sono simili a quella seguente.

 

 

Tab. 5.2: Seebeck emf di termocoppia tipo N secondo IEC (ITS 90).

 

Si può fare un confronto diretto con la normativa americana ASTM. Anche quest’ultima dà la tensione in uscita con intervalli di temperatura di 10 oC / oF.

 

 

5.2) Produttori.

 

Dalla seguente lista è possibile accedere ai siti dei principali rivenditori internazionali.

Alloy Engineering Manufacturers of Thermowells in Bridgeport Conn., USA

ARi Industries home page in The USA One of the thermocouple companies known for their specialty in very high temperature thermocouples.

ARi Industries(UK) Ltd home page

Biodata: Measurement and Control Index (in the UK)

Biodata: Thermocouple Tables (in the UK) for Accuracy

Branom/LITERATURE/thermocouple

CWC - Cabrera Wright Company

Carpenter Technology Home Page

Cobra Wire & Cable, Inc.

Controlco Products Page

Conax Buffalo Technologies, a leading USA manufacturer of temperature sensors including thermocouples and RTDs

EDL, Inc-Danville Virginia, USA,Temperature sensors, rtds, thermocouples, thermometer pyrometers also offer a wide range of value-priced temperature indicators and related specialty products

First Capitol Wire & Cable Co. Inc.

GlobalSpec - Temperature Sensor Search Form Help to FInd even more vendors of Thermocouples

Global Wire & Cable, Inc. Thermocouple and Extension Wire

Goodfellow Corp. Thermoelectric alloys in Berwyn, Penna., USA.

Hewitt Industries, Manufacturers of thermocouples

I2R - New Products makers of thermocouples, measuring and heating systems and controls.

Industrifil A manufacturer of miniature insulated wires and cables (copper and thermocouple) in France.

Instrument Service & Equipment, Inc. in Cleveland Ohio USA

THERMOCOUPLE TECHNICAL REFERENCE DATA including International Color (Colour) Codes -from ISE in Cleveland Ohio, USA.

Iron-Constantan (Type J) Thermocouples for instruments

Insulator Seal Inc

JC Controls

Laboratory Devices, Inc.

Labfacility Temperature Newsletter from the UK

Martin Metals

Minco Products. , Manufacturers of thermocouples and more in Minneapolis, Minn, USA

MTI Sensors Thermocouples, transmitters, wire &cable and much more in Lewisville, Texas, USA

Newport Thermocouples & Probes

AMSD Laboratory Capabilities at NASA in the USA.

Nanmac Corporation In Framingham, Mass. USA, makers of unique thermocouples and providers of an on-line catalog and detailed applications for thermocouples.

Omega Engineering -The giant of Catalog TC Sales and more in Conn and N.J, USA and elsewhere around the world.

Peak Sensors a TC maker and instrumentation supplier in the UK.

Power Associates, Inc.

Pyromation Inc's site pages where (downloadable) tables for non-USA standard TC types, RTD resistance vs temperature tables and specifications for several thermocouple and RTD types can be found.

Pyrotek, Inc. Thermocouples in Spokane, Washington, USA

Remspec Products

Sable Systems: Instrumentation Catalog

Sandelius Instruments, Inc. Multipoint thermocouples, bearing thermocouples, thermowells in Houston Texas, USA

SMI - The Medical Marketplace - Cryosurgical Instruments

Sparrell Engineering Research Corporation

Steinel Precise Temperature Control Home Page

STOLAB - Accurate Industrial Thermometers

TC Ltd in the UK

TechniCAL: Ecklund Thermocouple Receptacles

TemproxThermocouple and RTD assemblies in Lakeland, Fla., USA.

Temp-Pro Inc...Temperature Sensing Professionals, Northampton, Mass. in the USA

Thermo Electric Co. Inc, Thermocouple, Extension Wire, RTDs and more in Saddle Brook, NJ, USA

Thermometrics Corp., Thermocouples and RTDs for the process industries and OEMs in Northridge, Calif., USA and Extension Wire

Tools and Controls

Technical Industrial Products Thermocouples, RTDs, thermowells and more in Cherry Hill, NJ, USA

Watlow and Watlow-Gordon for thermocouples in the midwest, St. Louis, Mo., USA

XCO International, Inc.

York Wire

Mill for cold rolling of thermocouple cable

Thermocouples from Steve(?) in the UK

Thermocouple Technology Inc. Thermocouples in Quakertown, Penna., USA

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Preferred Suppliers


National Basic Sensor in Huntington Valley Penna. USA-for more than 28 years specializing in industrial thermocouples and RTDs

Marlin Manufacturing in Cleveland, Ohio ,USA

Pyromation Inc. Fort Wayne, Indiana, USA TC Supplier in No. Indiana and the holder of some unique web pages, including online TC calibration Tables!(USA)

THERMOCOUPLE TECHNICAL REFERENCE DATA including International Color (Colour) Codes -from ISE in Cleveland Ohio, USA.

JMS Southeast Statesville ,North Carolina, USA.... TC maker and supplier of all kinds of temperature sensors to industry and commerce from North Carolina USA

Thermo Kinetics Co. Inc, Mississauga ONT Canada- The knowledgeable