Thermocouple Cjc Compensation; Internal Automatic - Honeywell X Series User Manual

Thermocouple CJC Compensation

The different methods for connecting thermocouples according to the type of reference are
shown below.

Internal Automatic

Internal Auto
at this junction is being measured by a temperature sensor on the rear panel of the recorder.
The reading from this sensor is read off against a value taken from the thermocouple table,
which corresponds to the type of thermocouple being used. The corresponding reading in
volts for the temperature measured by the sensor is then used as a reference for the reading
from the thermocouple.
Diagram shows passive burnout, for active burnout replace the + for *.
286
Input terminals
on rear panel of
recorder
Measuring
junction
-
+
Thermocouple
cable
. This is connected to the input terminals of the recorder, and the temperature
Inputs
D
added
V
(C+D)
C
CJC Reading
in volts
A
Thermocouple
Table
Reading
°
in C
Look-up table
(Volts)
(converts
voltage read-
ing to tem-
perature)
Temperature
reading to
maths
expression
43-TV-25-30 Iss.6 GLO Aug 07 UK