A thermocouple is made from two dissimilar metal wires. The wires are are joined together at one end to form a measuring (hot) junction. The other end, known as the reference (cold) junction, is connected across an electronic measurement device (controller or digital indicator). A thermocouple will generate a measurement signal not in response to actual temperature, but in response to a difference in temperature between the measuring and reference junctions. A small ambient temperature sensor is built into the electronic measuring device near the point where the reference junction is attached. The ambient temperature is then added to the thermocouple differential temperature by the measuring device in order to determine and display the actual measured temperature.
Only two wires are necessary to connect a thermocouple to an electrical circuit; however, these connecting wires must be made from the same metals as the thermocouple itself. Adding wire made from other materials (such as common copper wire) will create new measuring junctions that will result in incorrect readings.
Selecting a Temperature Sensor
Style
TIPTEMP Temperature Sensors are available in a variety of styles. The weather- proofed screw cover style provides an electrical conduit connection and can be used to house a transmitter (optional). For open system sensing, a non-threaded style is offered. This design is provided with integrated lead wire and can be Teflon covered to protect the stem and lead wire against corrosive environments. A standard plug with a mating jack may also be furnished.
Stem (Sheath)
All TIPTEMP Thermocouples are furnished with a 316 stainless steel stem, with the internal wiring packed in powdered ceramic. The screw head cover style is available in two stem types: welded and spring loaded. The welded stem is suitable for use in liquid applications. The spring loaded stem is designed to bottom out inside a thermowell, providing maximum heat sensitivity. Spring loaded stems are not pressure tight and may allow process media to escape; therefore, they must always be installed in a thermowell.
Insertion (U) Length
The insertion (U) length of a thermocouple or represents its depth into the process vessel or thermowell. TIPTEMP Thermocouples and are available in standard U-lengths from 2" to 24". Other lengths are available upon special order, please consult factory.
Measuring (Hot) Junction
TIPTEMP Thermocouples are available in Types J, K, T, E & R/S and with ungrounded, grounded or exposed measuring junctions.
Connection (Termination)
TIPTEMP Thermocouples are provided with terminal block (screw cover head), mating jack, or integrated lead wire connections. The terminal block connection has no lead wire, therefore extension wire must be attached and routed to the electronic measuring device. Thermocouple extension wire must be identical to the thermocouple type, otherwise multiple measuring junctions will be made, causing inaccurate temperature readings.
Temperature Tools Catalog
Below are pages from our Red "Temperature Tools" Catalog. These pages will enable you to construct a part number for your particular sensor. When you have your part number call 1-800-847-8367 to get a price.
- View Laboratory & Industrial Process Thermocouples TC1 thru TC9.
- View Quick Disconnect Thermocouple Assemblies TC10, TC11.
- View Miniature Thermocouple Assemblies MTC10, MTC11, MTC16.
- View Heavy Duty Transition Thermocouple Assembliest TC16.
- View Lead Configuration For TC15, TC16, MTC16 & RTD16 Sensors.
- View Light Duty, Low Cost Thermocouple Assemblies TC14, TC15.
- View Fast Response Thermocouple Assemblies WTC, 6TC, SNA, SA.
- View Universal Bayonet Thermocouple Probes TC40, TC42.
- View Fixed Bayonet Thermocouple Probes TC50, TC51, TC52, TC53, TC54, TC55
- View Multi-Purpose 1/8" dia. Thermocouples TC44.
- View Pipe Clamp Thermocouples TC48.
- View Melt Bolt Thermocouples TC56, TC57, TC58, TC59.
- View Hand Held Thermocouples Assemblies TC70, TC71, TC71, TC73, TC74, TC75.
- View High Temp Exotic Thermocouple Assemblies HTC10, HMTC10, HTC16, HTC9
- View High Temperature Industrial Thermocouple Assemblies HTC1, HTE2
- View Heavy Duty Industrial Thermocouple Assemblies.TC20, TC21, PT19
- View Thermocouple / RTD Thermowell Assembly TC60, TC61, RTD62.
- View Ceramic Protection Tubes and Replacement Elements PT1, PT2, PT3, PT4.