Field Calibration with an Accurate Adjustable Resistance Source
1.1 Connect an Adjustable Resistance Source with an accuracy of 0.03% to the RTD
input terminals using a third sense wire.
For 2 wire sensors short terminal #1 to terminal #2.
1.2 Set the Type and Range for the RTD or resistance used in your application (DIP
switches #4, #6, #7 and #8). (RTD alpha=0.00385, Range 0 shown)
1.3 Set the FIELD CAL switch (#2) ON. [Current goes to 3.6 mA (nominal)]
1.4 Set the resistance source to the desired resistance for the 4 mA output. For 2 wire
sensors add the system lead resistance to the desired value.
1.5 Set the OUTPUT CAL switch (#1) ON. [Current stays at 3.6 mA (nominal)]
1.6 Adjust the input resistance up until the output equals 4 mA.
1.7 Set the OUTPUT CAL switch (#1) OFF. [Current increases to 22.3 mA (nominal)]
1.8 Set the resistance source to the desired resistance for the 20 mA output. For 2 wire
sensors add the system lead resistance to the desired value.
1.9 Set the OUTPUT CAL switch (#1) ON. [Current decreases to 20.5 mA (nominal)]
1.10 Adjust the input resistance down until the output equals 20 mA.
1.11 Set the OUTPUT CAL switch (#1) OFF.
1.12 Set the FIELD CAL switch (#2) OFF.
1.13 Disconnect the resistance source from the IRMA and connect the actual sensor to
be used in the application.
1
6
5
4
3
2
8
7
ON
1
6
5
4
3
2
8
7
ON
1
6
5
4
3
2
8
7
ON
1
6
5
4
3
2
8
7
ON
1
6
5
4
3
2
8
7
ON
1
6
5
4
3
2
8
7
ON
1
6
5
4
3
2
8
7
ON
Step 1.11
Step 1.12
Step
1
.
2
Step 1.3
Step 1.5
Step 1.7
Step 1.9
Power Supply
12 to 42 VDC
Current Display
4 to 20 mA
±
A
POWER/
6
OUTPUT
+
4
5
-
Indicator
Adjustable
3
1
2
Resistance
Source
RTD
S
-
+
MC2160X
IRMA
TEST
OUTPUT CAL
FIELD CAL
BASIC CAL
385/392
OPEN SEN DN/UP
RTD/OHMS
RANGE
RANGE
DIP SWITCH SETTINGS:
ON = 1
OFF = 0
M2161A
1
2
4
5
6
7
8
ON
Test
Pad
RED LION CONTROLS
MADE IN U.S.A.
MODEL IRMA
YORK, PA.
Field Calibration Wiring
Allow a 30 minute warm-up period before starting Field Calibration. Field
Calibration scales the 4 to 20 mA output to a temperature or resistance input.
This procedure assigns an input value to 4 mA and an input value to 20 mA. The
microprocessor handles configuring the output so it is linear to the temperature
or resistance input. The Field Calibration procedure is described below.
Note: The unit needs to have the Field Calibration completed by the operator
before normal operation. To abort this calibration and reset to the previous
settings, set the FIELD CAL switch OFF prior to the final OFF setting of the
OUTPUT CAL switch (Step 1.11) and turn off power. Wait 5 seconds and then
turn on power and the previous settings will be loaded.
RTD temperature to resistance conversion table
CALIBRATION PROCEDURES
1.0 Field Calibration
Temperature
C
alpha
0.00385 ohms
Temperature
°C
alpha
0.00385 ohms
alpha
0.00392 ohms
-160
alpha
0.00392 ohms
35.53
300
212.03
214.08
-150
34.38
39.71
350
229.69
232.07
-100
60.25
38.64
400
247.05
249.77
-50
80.30
59.55
410
250.49
253.28
0
79.96
100.00
450
264.13
267.18
50
119.40
100.00
500
280.92
119.75
284.30
100
138.5
139.20
550
297.42
301.13
150
157.33
158.36
590
310.41
314.38
190
172.17
173.48
600
313.63
317.66
200
175.85
177.23
640
326.38
330.68
250
194.09
195.80
650
329.54
333.90
4
AUDIN - 8, avenue de la malle - 51370 Saint Brice Courcelles - Tel : 03.26.04.20.21 - Fax : 03.26.04.28.20 - Web : http: www.audin.fr - Email : [email protected]
