UTC Fire and Security Det-Tronics R8471B Instructions Manual page 13

The sensor must be oriented with the filter pointing
down. Position the junction box with the conduit
connected to the upper opening. The sensor will be
installed in the lower opening on the junction box.
3. Remove the cover from the junction box.
Do not apply power to the system with the junction
box cover removed unless the area has been de-
classified.
4. Remove the cap from the sensor housing. See
Figure 6.
5. Remove the sensing element assembly from its
packaging. Determine proper orientation for the
assembly, then carefully plug it into the sensor
housing.
Handle the sensing element assembly carefully.
To avoid possible damage, observe the normally
accepted procedures for handling electrostatic
sensitive devices. See form 75-1005 for additional
information.
6. Place the cap back on the sensor housing.
Tighten only until snug. Do not over tighten.
7. Attach the sensor to the junction box. The sen-
sor should be tight to ensure an explosion-proof
installation, however, do not over tighten.
2.1
NOTE
NOTE
SENSOR HOUSING
Figure 6—Exploded View of Sensor
Coat the sensor threads with an appropriate
grease to ease installation, and also lubricate the
junction box cover threads to ensure a water-
tight enclosure. The recommended lubricant is a
silicone free polyalphaolefin grease, part number
005003-001, available from Detector Electronics.
8. Connect the sensor wires to the terminal block
marked "to sensor." (See Figure 7.) Connect the
controller wiring to the terminal block marked "to
controller." Connect the shield to earth ground at
the controller. Under normal conditions, the other
end of the shield should not be connected at the
sensor junction box unless such a connection is
required by local wiring codes.
The wiring code is:
Red lead
Black lead
Green lead = Chassis (earth) ground.
In order to maintain the intrinsically safe rating of the
C7064C Sensor, it must be wired through an approved
I.S. barrier. See Figure 8.
When an I.S. barrier is used, the input voltage
(measured at the controller) must be between 23
and 26.6 vdc to ensure proper operation of the
sensor and barrier.
SENSING ELEMENT ASSEMBLY
11
NOTE
= "+"
= "–"
NOTE
CAP
HYDROPHOBIC FILTER
B1203
95-8401