Red Lion ITMA - Manual (Page 5)

5
12 to 42 VDC
Power Supply
± 4 to 20 mA A
Indicator
Current Display
POWER/
OUTPUT
M2068B +
4 5
-
6
Thermometer
+
TC
-
1 2 3
Source
+ -
Precision
Millivolt
Adjustable
ITMA
Ice Point Calibration Wiring
1 2 3 4 5 6 7 9 8 10
ON
1 2 3 4 5 6 7 9 8 10
ON
1 2 3 4 5 6 7 9 8 10
ON
ON
1 2 3 4 5 6 7 9 8 10
Step 3.1
Step 3.5
Step 3.5
Step 3.6
3.0 Ice Point Calibration
The Ice Point Calibration should only be performed with an ambient temperature
between 21°C and 29°C. This Calibration was performed on the unit at the factory during
the Basic Calibration and generally does not need to be done again. The Ice Point
Compensation can be adjusted through this calibration. The Ice Point Calibration
procedure is described below.
Note: Calibration can be aborted by setting the BASIC CAL switch OFF prior to the
setting of the OUTPUT CAL switch OFF. (Step 3.6)
3.1 Connect a precision mV source with an accuracy of 0.02% to Terminal #1 TC+ Input
and Terminal #2 TC- Input. Set the OUTPUT CAL switch (#1) and ICE PT EN/DIS
switch (#4) OFF. Set the BASIC CAL (#3) and FIELD CAL (#2) switches ON. The
positions of switches #5 thru #10 are not relevant for this calibration procedure.
3.2 Connect a precision thermometer (accuracy of 0.1°C) to the unused terminal (#3)
beside the TC Input terminals.
3.3 Apply power and allow a 30 minute warm-up period. [Current goes to 3.5 mA
(nominal)]
3.4 Using the temperature indicated by the precision thermometer, input an equivalent
1 mV/°C signal to the TC Input terminals and wait 5 seconds.
3.5 Set the OUTPUT CAL switch (#1) ON and then OFF.
3.6 Set the BASIC CAL switch (#3) and FIELD CAL switch (#2) OFF. [Current
increases to 3.6 mA (nominal) or more]
TEST
OUTPUT CAL
FIELD CAL
BASIC CAL
ICE PT EN/DIS
OPEN SEN DN/UP
TC TYPE
TC TYPE
TC TYPE
RANGE
RANGE
DIP SWITCH SETTINGS:
ON = 1 OFF = 0 M2069A
1
2
4
5
6
7
8
9
10
ON
Test
Pad
RED LION CONTROLS
YORK, PA. MADE IN U.S.A.
MODEL ITMA