Omron E5GC User Manual page 353

Additional Information
Connecting the Cold Junction Compensator
Correct process values cannot be obtained if you touch the contact ends of the compensating
conductor during calibration of a thermocouple. Accordingly, short-circuit (enable) or open
(disable) the tip of the thermocouple inside the cold junction compensator as shown in the figure
below to create a contact or non-contact state for the cold junction compensator.
E5@C
Compensating conductor
In this example, calibration is shown for a Digital Controller with thermocouple/infrared temperature
sensor set as the input type.
adj
30
• Input types 5, 7, 11, 12,
15, 19, 20:
t 54
69as
• Input types 6, 8, 9, 10, 13,
14, 16, 17, 18, 21, 22, 23,
24:
t 24
e220
E5@C Digital Temperature Controllers User's Manual (H174)
Cold junction compensator
Short-circuit
0°C/32°F
1. Connect the power supply.
2. Connect a standard DC current/voltage source (STV), precision digital multimeter
(DMM), and contact junction compensator (e.g., a zero controller as in the figure)
to the thermocouple input terminals, as shown in the figure below. When you
calibrate the E5@C-B or E5GC, connect STV and DMM through the terminal
block.
E5CC, E5CC-U, E5EC, E5AC, or E5DC
Leave open.
STV
DMM
Zero controller
OUTPUT
3. Turn the power ON.
4. Move to the Calibration Level.
This starts the 30-minute aging timer. This timer provides an approximate timer for
aging. After 30 minutes have elapsed, the No. 2 display changes to 0. You can
advance to the next step in this procedure even if 0 is not displayed.
5. When the M Key is pressed, the status changes as shown to the left.
The No. 2 display at this time shows the currently entered count value in
hexadecimal. Set the STV as follows:
• Input types 5, 7, 11, 12, 15, 19, 20: Set to 54 mV.
• Input types 6, 8, 9, 10, 13, 14, 16, 17, 18, 21, 22, 23, 24: Set to 24 mV.
Allow the count value on the No. 2 display to fully stabilize, then press the D Key to
temporarily register the calibration settings.
If this count value is outside of the specified range, the No. 2 display will flash and
the count value will not be temporarily registered.
Cold junction compensator
0°C/32°F
E5@C
Compensating conductor
Leave open.
−
+
INPUT OUTPUT
Compensating conductor of currently selected
thermocouple
Use K thermocouple compensating conductor for E, R,
S, B, W, and PLII thermocouples and for an infrared
temperature sensor.
7 User Calibration
Open
E5@C-B or E5GC
Relay terminal block
STV
−
DMM
+
Zero controller
INPUT
7
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