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©Copyright 2019 Dwyer Instruments, Inc.
Printed in U.S.A. 1/19
FR# 443800-20 Rev. 3
MAINTENANCE/REPAIR
Upon final installation of the Series CDT and CDTR, no routine maintenance is
required. The Series CDT and CDTR are not field serviceable and should be returned
if repair is needed. Field repair should not be attempted and may void warranty.
WARRANTY/RETURN
Refer to “Terms and Conditions of Sales” in our catalog and on our website. Contact
customer service to receive a Return Goods Authorization number before shipping the
product back for repair. Be sure to include a brief description of the problem plus any
additional application notes.
Series
CDT -2 N 4 4 -LCD Example: CDT-2W44-LCD
Range
2
5
0 to 2000 ppm CO
2
range
0 to 5000 ppm CO
2
range
Configuration
W
Wall
CO
2
Output
4
4 to 20 mA / 0 to (5 or 10) VDC
Temperature
Output
0
4
A
B
C
D
E
F
None
4 to 20 mA / 0 to (5 or 10) VDC
10 KΩ NTC thermistor type III
10 KΩ NTC thermistor type II
3 KΩ NTC thermistor
Pt100 Ω RTD
Pt1000 Ω RTD
20 KΩ NTC thermistor
Options
LCD
RLY
NBC
LCD display
Relay
No buttons
US Customary Units
ft
in Hg
0
400
800
1200
1600
2000
2400
2800
3200
3600
4000
4400
4800
5200
5600
6000
6400
6800
7200
7600
8000
8400
8800
9200
9600
10000
29.92
29.50
29.10
28.69
28.29
27.90
27.51
27.13
26.76
26.39
26.02
25.66
25.30
24.95
24.60
24.26
23.93
23.60
23.27
22.94
22.63
22.31
22.00
21.70
21.40
21.40
SI Units
m
hPa
0
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
1500
1600
1700
1800
1900
2000
2100
2200
2300
2400
2500
1013
1002
990
979
968
957
946
935
924
914
904
893
883
873
863
853
844
834
824
815
806
797
787
779
770
761
Series
CDTR -2 W 4 A 4 -LCD Example: CDTR-2W4A4-LCD
Range
2
5
0 to 2000 ppm CO
2
range
0 to 5000 ppm CO
2
range
Configuration
W
Wall
CO
2
Output
4
4 to 20 mA / 0 to (5 or 10) VDC
Temperature
Output
0
A
B
C
D
E
F
None
10 KΩ NTC thermistor type III
10 KΩ NTC thermistor type II
3 KΩ NTC thermistor
Pt100 Ω RTD
Pt1000 Ω RTD
20 KΩ NTC thermistor
RH Output
4
4 to 20 mA / 0 to (5 or 10) VDC
Options
LCD
RLY
NBC
LCD display
Relay
No buttons
Temperature Resistance Curves (in Ohms)
°C °F
A
B
C
D
E
F
-55
-50
-45
-40
-35
-30
-25
-20
-15
-10
-5
0
5
10
15
20
25
30
35
40
45
50
55
60
65
70
75
80
85
90
95
100
105
110
115
120
125
130
135
140
145
150
-67.0
-58.0
-49.0
-40.0
-31.0
-22.0
-13.0
-4.0
5.0
14.0
23.0
32.0
41.0
50.0
59.0
68.0
77.0
86.0
95.0
104.0
113.0
122.0
131.0
140.0
149.0
158.0
167.0
176.0
185.0
194.0
203.0
212.0
221.0
230.0
239.0
248.0
257.0
266.0
275.0
284.0
293.0
302.0
607800.00
441200.00
323600.00
239700.00
179200.00
135200.00
102900.00
78910.00
61020.00
47540.00
37310.00
29490.00
23460.00
18780.00
15130.00
12260.00
10000.00
8194.00
6752.00
5592.00
4655.00
3893.00
3271.00
2760.00
2339.00
1990.00
1700.00
1458.00
1255.00
1084.00
939.30
816.80
712.60
623.60
547.30
481.80
425.30
376.40
334.00
297.20
265.10
237.00
963849.00
670166.00
471985.00
336479.00
242681.00
176974.00
130421.00
97081.00
72957.00
55329.00
42327.00
32650.00
25392.00
19901.00
15712.00
12493.00
10000.00
8057.00
6531.00
5326.00
4368.00
3602.00
2986.00
2488.00
2083.00
1752.00
1480.00
1255.00
1070.00
915.50
786.60
678.60
587.60
510.60
445.30
389.60
341.90
301.00
265.80
235.30
208.90
186.10
289154.70
201049.80
141595.50
100943.70
72804.30
53092.20
39126.30
29124.30
21887.10
16598.70
12698.10
9795.00
7617.60
5970.30
4713.60
3747.90
3000.00
2417.10
1959.30
1597.80
1310.40
1080.60
895.80
746.40
624.90
525.60
444.00
376.50
321.00
274.65
235.98
203.58
176.28
153.18
133.59
116.88
102.57
90.30
79.74
70.59
62.67
55.83
78.32
80.31
82.29
84.27
86.25
88.22
90.19
92.16
94.12
96.09
98.04
100.00
101.95
103.90
105.85
107.79
109.74
111.67
113.61
115.54
117.47
119.40
121.32
123.24
125.16
127.08
128.99
130.90
132.80
134.71
136.61
138.51
140.40
142.29
144.18
146.07
147.95
149.83
151.71
153.58
155.46
157.33
783.2
803.1
822.9
842.7
862.5
882.2
901.9
921.6
941.2
960.9
980.4
1000.0
1019.5
1039.0
1058.5
1077.9
1097.4
1116.7
1136.1
1155.4
1174.7
1194.0
1213.2
1232.4
1251.6
1270.8
1289.9
1309.0
1328.0
1347.1
1366.1
1385.1
1404.0
1422.9
1441.8
1460.7
1479.5
1498.3
1517.1
1535.8
1554.6
1573.3
2394000.00
1646200.00
1145800.00
806800.00
574400.00
413400.00
300400.00
220600.00
163500.00
122280.00
92240.00
70160.00
53780.00
41560.00
32340.00
25360.00
20000.00
15892.00
12704.00
10216.00
8264.00
6722.00
5498.00
4520.00
3734.00
3100.00
2586.00
2166.00
1822.60
1540.00
1306.40
1112.60
951.00
815.80
702.20
606.40
525.60
N/A
N/A
N/A
N/A
N/A
Figure 8: CDT Model Chart
Figure 7: Calibration
Figure 9: Elevation Chart
Figure 10: Resistance vs Temperature
RESISTANCE VS TEMPERATURE TABLE
Figure 9: CDTR Model Chart
CO
2
SENSOR
This symbol indicates waste electrical products should not be disposed
of with household waste. Please recycle where facilities exist. Check with
your Local Authority or retailer for recycling advice.
DWYER INSTRUMENTS, INC.
P.O. BOX 373 • MICHIGAN CITY, INDIANA 46360, U.S.A.
Phone: 219/879-8000
Fax: 219/872-9057
dwyer-inst.com
e-mail: [email protected]