CHAPTER 7 CALIBRATION
E5AK
7--4
7.2 Calibrating Thermocouple
·
Calibrate according to the type of thermocouple, thermocouple 1 group
(K1, J1, L1, E, N, W, PLII) and thermocouple 2 group (K2, J2, L2, R, S,
B, T, U).
·
When calibrating, do not cover the bottom or top of the controller. Also,
do not touch the input terminals (Nos. 11 and 12) and compensating con-
ductor on the E5AK controller.
F
Preparations
10
9
8
7
6
5
4
3
2
1
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
15
14
13
12
11
31 32
33
DMM
STV
Cold junction
compensator
0
_
C/32
_
F
Compensating
conductor
SOURCE
AC100-240V
(AC/DC24V
)
~
·
Set the cold junction compensator to 0
_
C. However, make sure that
internal thermocouples are disabled (tips are open).
·
In the above figure, STV refers to a standard DC current/voltage source,
and DMM refers to a precision digital multimeter.
However, note that DMM is required only when the transfer output
function is supported.
·
Use the compensating conductor selected thermocouple. However, note
that when thermocouple R, S, E, B, W or PLII is used, the cold junetion
compensator and the compensating conductor can be substituted with
the cold junction compensator and the compensating conductor for
thermocouple K.
Correct process values cannot be obtained if you touch the contact ends of the com-
pensating conductor during calibration of a thermocouple. Accordingly, short
(enable) or open (disable) the tip of the compensating conductor inside the cold junc-
tion compensator as shown in the figure below to create a contact or non-contact
state for the cold junction compensator.
Connecting the
Cold Junction Con-
ductor
0
°
C/32
°
F
0
°
C/32
°
F
Cold junction
compensator
Cold junction
compensator
E5AK
controller
E5AK
controller
Compensating conductor
Compensating conductor
Short
Open