Chapter 8 Tutorial

Measurement Fundamentals

I z y ut uq usu uu .6°L/4 Ysu u uvuusu uqu qt u°s”u u qu “

°uqu u °uqu°u”u sq4

Internal DMM

Ice Bath

 

dxu d3 xu°s”u y q y squ yu u xu s

MWW’s input terminals.

.su y u °u u yq”

If another type of thermocouple is used, two additional thermocouples are created. For example, take a look at the connections with a J-type thermocouple (iron and constantan):

Internal DMM

Ice Bath

Two additional thermocouples have been created where the iron (Fe) lead connects to the internal MWW’s copper (Cu) input terminals. Since these two junctions will generate opposing voltages, their effect will be to cancel each other. However, if the input terminals are not at the same temperature, an error will be created in the measurement.

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HP 34970A manual Internal DMM Ice Bath