Detcon IR-642 - Manual (Page 10)

Consideration should be given to easy access by maintenance personnel as well as the consequences of close prox-
imity to contaminants that may foul the sensor prematurely.
Note: An appropriate conduit seal must be located within 18" of the sensor assembly. Crouse Hinds type EYS2,
EYD2 or equivalent are suitable for this purpose.
3.5.5 Installation Procedure
Note: See section 3.5.6 for special information on remote mounting applications in which the sensor (Model IR-
640-RS) is remotely mounted away from the transmitter (Model IR-640-RT).
a) Remove the junction box cover and un-plug the control circuit by grasping the two thumb screws and pulling outward.
b) Securely mount the sensor junction box in accordance with recommended practice. See dimensional drawing (Fig. 2).
c) Observing correct polarity, terminate 3 conductor field wiring, RS-485 wiring, and applicable alarm wiring to the
sensor base connector board in accordance with the detail shown in Figure 3. Normally open and normally closed
Form C dry contacts (rated 5 amp @ 120VAC; 5 amp @ 30VDC) are provided for Fault, Alarm 1, and Alarm 2.
d) Position gold plated jumper tabs located on the connector board in accordance with desired Form C dry con-
Detcon Model IR-640/IR-642 Carbon Dioxide Sensor PG.10
NC
ALARM 1
W
H
T
B
L
K
Y
E
L
B
LU
MA
VDC Power In
Optional RS-485
Terminating Resistor
Use 120 ohm
NO
NC
NO
NC
NO
N
O
/N
C
C
O
M
N
O
/N
C
C
O
M
N
O
/N
C
C
O
M
FAULT ALM-2 ALM-1
Alarm Dry Contacts
ALARM 2
FAULT
R1
R2
A
B
A
B
4-20 mA Output
RS-485 In
RS-485 Out
Optional 4-20 mA
Signal Developing Resistor
Use 250 ohm 1/4w
JU
M
P
E
R
S
U
N
-U
S
E
D
R
E
D
B
R
N
Jumper Programmable Alarm Outputs
Normally Open or Normally Closed
Sensor
Place un-used alarm programming
jumper tabs here
Figure #3
4 3/4"
3/4" NPT
1/4" Dia.
Mounting Holes
8 1/4"
6 1/8"
5 1/2"
3/4" NPT
Rainshield/
Splashguard
2"
2 1/8"
Figure #2