Chell FlightDaq-TL, Инструкция по установке и эксплуатации

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4.3 Thermocouple Inputs
The FlightDaq-TL can only measure thermocouples when used in conjunction
with the Chell Smart Lemo®. The Smart Lemo® forms the cold junction of the
thermocouple by crimping the thermocouple alloy to copper tubes. The
temperature of this junction is then measured by a 10kΩ thermistor which is
bonded to the copper tubes. There is an (optional) internal memory within the
Smart Lemo® which can carry the calibration of the thermocouple and/or the
thermistor.
For all thermocouple ranges, the primary input is set to ±78mV to measure the
hot junction and the secondary input is set to 5V which, when combined with the
excitation will measure the output of the thermistor.
The results from the two inputs are converted to temperature by using the
appropriate NIST look-up-tables for both the hot junction and the thermistor.
This is all configured automatically when the thermocouple input is selected.
Configuration
Number
Type
Code
Type
Variant
Range
Pri Range Sub Range Excitation
17 11 Thermocouple B 78mV 5V 10kΩ
18 12 Thermocouple E 78mV 5V 10kΩ
19 13 Thermocouple J 78mV 5V 10kΩ
20 14 Thermocouple K 78mV 5V 10kΩ
21 15 Thermocouple N 78mV 5V 10kΩ
22 16 Thermocouple R 78mV 5V 10kΩ
23 17 Thermocouple S 78mV 5V 10kΩ
24 18 Thermocouple T 78mV 5V 10kΩ