1. Thermocouples (TC) acc.DIN IEC 60584 / DIN 43710 1.1 Introduction Thermocouples are active contact sensors that find wide applications in industrial measuring and control technology because of their almost indefinite small structure forms and a very large temperature range from -200°C to +1700°C (or 2300°C). They are especially useful in the construction of systems, machines and devices. They are also used in molten salt and metal treatment. In many high temperature applications they are a low cost alternative to devices operated by radiation. 1.2 Fundamentals The temperature to be measured...

1.3.2 Thermocouple A thermocouple consists of Thermo two different metal Norm Alloy short signs Material names couples conductors, the so called Cu - CuNi Copper - Constantan thermal legs, which are joined Type T with each other at the Type E NiCr - CuNi Chromel - Constantan measuring point. Out of many Type J Fe - CuNi Iron - Constantan possibilities for combining IEC 60584 Ni - CrNi Type K Chromel - Alumel materials that are electric Pt10%Rh - Pt Platinum/Rhodium - Platinum conductors, relatively few are Type S Pt13%Rh - Pt Platinum/Rhodium - Platinum suitable for building Type R Type B Pt30%Rh...

EPHY MESS Gesellschaft fur Elektro-Physikalische MeBgerate mbH 1.4 Basic values of thermal voltages and tolerances The temperature - voltage values (basic values) of the shelf thermocouples are quated in the DIN 43710 and IEC 60584 norms. Thermocouples are classified by the maximum permissible deviation from these basic values. A complete table of basic values is in the appendix of this catalogue. Table 2: Tolerance classes EPHY-MESS normally delivers thermocouples and wires from tolerance class 2. Delivery of goods from classes 1 and 3 is possible on request. For the tolerances of thermocouples...

1.7 Operation conditions To maintain high measurement accuracy of thermocouples over long periods of time, it is necessary to select them carefully for their intended use. Two factors are very important: maximum temperature and medium to be measured in. A Ni-CrNi thermocouple (type K) is, for example, highly resistant to oxidizing agents, but if it is heated to over 850°C then its thermal electric properties change in such a way that even at low temperatures (<0°C) there are residual deviations. Thermal pairs of types J and L, which are made Fe-CuNi, are threatened by oxidizing agents at above...

1.8 Product line overview Table 3: TC product line EPHY-MESS Thermocouples

2. Extension grade wires Extension grade wires (= substitute materials for the thermoelectric wires with equal thermo electric properties) are usually used in the following cases: • the use of an uninterrupted thermoelectric wire is technically not possible (e.g. thermocouple with connector head or ducts) • the original thermoelectric wires does not have sufficient mechanical stability • the resistance of the original thermoelectric wires is too high for the measuring circuit • significant cost reduction in the case of the thermoelectric wires of noble metals The following extension grade wires...

EPHY MESS Gesellschaft fur Elektro-Physikalische MeBgerate mbH 2.2 Thermocouples with bare (naked) measuring point This is the simplest version acc. DIN 43732, structure C and D. The extension grade or thermoelectric wire can remain bare or might be insulated over the entire length of the thermocouple, excluding the measuring bead. 2.3 Thermocouple with insulated measuring point i.e. coil head thermocouples (TE-WK) This type of configuration has its origin and main application range in the electric motors, generators, and transformers industries. Because of its compact form and insulation, these...

EPHY MESS Gesellschaft fur Elektro-Physikalische MeBgerate mbH 2.5 Coil head thermocouple, cemented in ceramic or metal sheaths (TE-WK-KH / -MH) This type already has high mechanical resistance, and it is easy to install the sensors. The advantage of small dimensions with fast response time remains. The sheathing materials available include all common metals as well as ceramics. insulating material / measuring bead protection Tabelle 5: Technical data TE-WK-KH / MH 2.6 Coil head thermocouple, cemented in screw-in housing (TE-WK-ESF) This one is especially suitable for measuring surface temperatures...

EPHY MESS Gesellschaft fur Elektro-Physikalische MeBgerate mbH 3. Slot thermocouple (TE-NT) This construction form is equivalent to the rigid Pt100 slot resistance thermometer in regard to insulation, dimensions and ranges of operation (within the coils of electromotors, generators and transformers). While the slot resistance thermometer has greater precision of measurement (+/- 0.3°C), the slot thermocouple has a shorter response time. Because of the special inner structure with copper sheet for heat contact between the measuring point and its surroundings, temperature can be measured over a...

EPHY MESS Gesellschaft fur Elektro-Physikalische MeBgerate mbH 4. Pad thermocouples (TE-FPI) 4.1 Application range Stick-on pad thermocouples have been specially designed for measurements on surfaces. Hence their application ranges lie in research, development and manufacture, where, for example, temperature distribution and gradients in housing, heat utilization must be measured quickly, or where no space is available for larger thermometers. Pad thermocouples offer the following advantages: • high flexibility • small dimensions (7 x 7 x 0.16 mm) • low response times (as low as 0.06s) • simple...

EPHY MESS Gesellschaft fur Elektro-Physikalische MeBgerate mbH 5. Plug-in thermocouple (TE-EST) 5.1 General Plug-in thermocouples are used to measure or regulate temperatures in ranges up to 400°C, for example, in • polymer processing machines • injection moulding machines • cylinder heads and oil tubs of motors • bearings • pipelines and containers • generators and transformers They are usually plugged into machine bores parts and are easy to replace. 5.2 Structure EPHY-MESS plug-in thermocouple, which have good response times, absorb heat via the highly heat conductive base of the protective...