Reference Multimeter and 8 ½ Digit Multimeter
Thermocouple
73
In this example, the Fluke 5522A simulator and the Product are both set to a J-
type thermocouple (constantan and iron). You must use the correct J-type
hookup wire and connector between the DUT and the cold junction. The
connection from the cold junction to the Product must be with copper wire.
Instead of the zero-point dry-well, a dewar with an ice/water slurry mixture can
also be used. For the best accuracy, and to get good test-uncertainty-ratios
(TURs) against the most demanding thermocouple simulators, use an external
reference thermometer to characterize the Fluke 9101 or ice/water slurry mixture.
The connections to calibrate actual thermocouples also requires an external cold
junction. Use a setup that uses a zero-point dry well as in Figure 21, or make an
external cold junction with a dewar and ice bath as in Figure 22. A J type
thermocouple (constantan and iron) is shown. Copper wires are used to connect
from the cold junction to the Products V INPUT HI and LO terminals. The ice bath
reference in this example is comprised of a dewar with an ice/water slurry
mixture. See Figure 22.
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Figure 22. Thermocouple Circuit to Calibrate J-type Thermocouple
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