Thermocouple temperature accuracy test, Open thermocouple response test – Fluke NetDAQ 2645A User Manual
Page 188
2640A/2645A NetDAQ
Users Manual
6-16
Thermocouple Temperature Accuracy Test
6-15.
Ensure that the Accuracy Tests (above) have been completed before performing
this test.
1.
Connect a Thermocouple Remove the Universal Input Module from the
instrument and connect the supplied type T thermocouple to the channel 1
terminals with the blue lead to the H terminal and red lead to the L terminal.
Reinstall the Universal Input Module.
2.
Configure Channel 1 for Thermocouples In NetDAQ Logger, configure
channel 1 for Thermocouples with Range (thermocouple type) T. (See
“Configuring Analog Channel Functions" in Chapter 3 of this manual.)
3.
Open Spy Window Select the Spy command from the Utilities menu. Select
analog channel 01. Click OK to open the Spy window.
4.
Verify Accuracy Insert the thermocouple and a mercury thermometer in a
room-temperature bath. Allow 20 minutes for thermal stabilization. The value
displayed on the mercury thermometer should equal the value in the Spy
Window + 0.5
°
C (2640A) or + 0.95
°
C (2645A) plus any sensor inaccuracies.
5.
Close Spy Window.
Open Thermocouple Response Test
6-16.
This test checks the Open Thermocouple response.
1.
Connect an 820 Ohm Test Resistor Remove the Universal Input Module
from the instrument and connect an 820 ohm resistor to the channel 1
terminals. Reinstall the Universal Input Module.
2.
Configure Channel 1 for Thermocouples In NetDAQ Logger, configure
channel 1 for Thermocouples with Range (thermocouple type) K. (See
“Configuring Analog Channel Functions" in Chapter 3 of this manual.)
3.
Open Spy Window Select the Spy command from the Utilities menu. Select
analog channel 1. Click OK to open the Spy window. The value displayed
should approximate the ambient temperature.
4.
Connect a 10k Ohm Test Resistor Remove the Universal Input Module
from the instrument and connect a 10k ohm resistor to the channel 1 terminals
to simulate an open thermocouple condition. Reinstall the Universal Input
Module.
5.
Verify Open Thermocouple The Spy window indicates an open
thermocouple detect condition by displaying Open TC in place of a
temperature reading.
6.
Close Spy Window.