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W A T L O W

KN A thermocouple alloy made of 95 percent nickel, two percentaluminum, two percent manganeseand one percent silicon that is used inthe negative conductor of ASTM Type K thermocouples. Manufacturer trademarks for KN include Alumel

Application Guide catalog - 7347 Glossary

job A set of operating conditions for aprocess that can be stored andrecalled in a controller’s memory. Also called a recipe. IP One of two primary protocols thatinternet hosts use. IP describes themessage packet (datagrams orsegment of messages) format. IP isnetwork layer protocol defined by the IETF. See “TCP” and “TCP/IP.” Joint Industrial Standards (JIS) AJapanese agency that establishes andmaintains standards for equipmentand components. Also known as JISC(Japanese Industrial Standards Committee), its function is similar toGermany’s Deutsche Industrial Norm(DIN). IPTS48, 68 International PracticalTemperature Scales of 1948 and 1968.These have been superseded by ITS90. See “ITS90.”
® iron The positive conductor in ASTMType J thermocouples. Joule A basic unit of heat energy,equal to the work done when a currentof one ampere is passed through aresistance of one ohm for one second. ,Nial
® and HAI-KN
® . ISA See “Instrument Society ofAmerica.” KP A thermocouple alloy made of 90percent nickel and 10 percentchromium that is used in the positive conductors of ASTM Type E and K thermocouples. Manufacturer trademarks for KP include Chromel isolation junction A form ofthermocouple probe construction inwhich the measuring junction is fully enclosed in a protective sheath andelectrically isolated from it. Commonlycalled an ungrounded junction. junction The point where twodissimilar metal conductors join to forma thermocouple.
® ,Tophel
® and HAI-KP
® . isolation Electrical separation ofsensor from high-voltage circuitry.Allows use of grounded or ungrounded sensing element. kVA Kilovoltampere or 1,000voltamperes (VA). One unit of apparentpower equals 1VA. isothermal A process, volume or areathat maintains a constant temperature. k-value The measure of a material'sthermal conductivity coefficient or itsability to conduct heat. Copper conducts better than plastic; copper has a higher k value. The k-value is expressed in W/cmK (watt per centimeter Kelvin) or in Btu/hft.F (Btu per hour per ft. degree Fahrenheit). The k-value is the reciprocal of the R- value, thermal resistance. ITS90 International Temperature Scaleof 1990. The standard scale made offixed points that closely approximatethermodynamic temperatures. All temperatures between the fixed pointsare derived by interpolation using theassigned interpolation instrument. Adopted in late 1993, this scalereplaces both IPTS48 and 68.

K

Kapton
® A lightweight organicpolymer film that is a versatiledielectric material because of itstensile strength, dimensional stability and low emission of gas in vacuums. A registered trademark of the E.I. duPont de Nemours & Company. Kelvin (k) An absolute temperaturescale. Zero Kelvin is absolute zero. No degree symbol (°) is used with theKelvin scale. (0°C = 273.15K, 100°C = 373.15K).
Glossary kilo (k) A prefix meaning thousand. kilowatt (kW) Unit of electrical powerequal to 1,000 watts or 3,412 Btus perhour when the power factor equals 1.0.

L

LA Lead Adaptor. Watlow's patentedmethod for adding a variety of optionsfor leads and lead protection to stock heaters. kilowatt hour (kWh) Unit of electricalenergy, or work, expended by onekilowatt in one hour. Also expressed as 1,000 watt hours. ladder logic An electrical circuitdiagram schematic style that arrangesthe positive and negative sides of thepower input as the two main beams of a vertical ladder, and arranges theconnections between them as therungs of the ladder.

J

jacket The outer covering on a wire orcable. It may provide electricalinsulation and/or resistance to chemicals, abrasion and moisture. lag The amount of time delay betweentwo related parts of a process orsystem. JDA Joint Development Agreement.Specifies what role each party agreesto when developing a new product. JIS See “Joint Industrial Standards.”
Nial ® and Tophel ® are registered trademarks ofCarpenter Technology (Car Tech).Chromel ® and Alumel ® are registeredtrademarks of Hoskins Manufacturing Company.HAI-KN ® and HAI-KP ® are registeredtrademarks of Harrison Alloys Company. 199