Det-Tronics U7602B-P Unitized UV Flame Detector/Controller User Manual
Page 13
2.
If the unit is equipped with a cover locking clamp,
loosen it with a 5/32 hexagonal (Allen) wrench
and move the clamp “catches” out of the blind
holes located in the bulkhead. See Figure 16.
3.
Remove the controller housing and sensor hous-
ing from the bulkhead by turning them counter-
clockwise.
NOTE
The U7602 contains semiconductor devices that
are susceptible to damage by electrostatic dis-
charge. An electrostatic charge can build up on
the skin and discharge when an object is
touched. Therefore, use caution when handling
the U7602, taking care not to touch the terminals
or electronic components.
4. Route the field wiring through the detector conduit
entry. Refer to Figure 13 for wiring a single unit
and Figure 14 for a multiple configuration using
end of line resistors. Figure 15 shows a multiple
configuration using end of line capacitors.
IMPORTANT
Current limiting resistors must be used as shown
in Figure 15 when using end of line capacitors.
Failure to do so can result in the relay contact
ratings being exceeded, and subsequent welded
relay contacts.
5. Connect the power wires to terminals + (H) and –
(N) on TB1 inside the housing, ensuring that the
proper polarity is observed. Voltage require-
ments for each unit are printed on the label on the
sensor housing and on the top of the controller
module. Figure 10 shows TB1 connections
(power, circuit ground and oi). If the earth
ground wire is used, it should be connected to
the chassis ground screw (GND) provided (this is
not located on TB1).
6. To use the manual oi feature, connect a normally
open switch between circuit ground and the oi
TEST terminal on TB1. Each U7602 must have its
own oi test switch.
7. If the current signal output is used, it must be in a
separate shielded cable. Connect the shield of
this cable to the CKT GND terminal on TB1.
10
+
TB3
*
FIRE ALARM PANEL
ALARM
INPUT
U7602
U7602
EOL
CAPACITOR
CURRENT
EXTERNAL CURRENT METER
(IF NEEDED)
FIRE RELAY IS NORMALLY OPEN.
FAULT RELAY IS NORMALLY CLOSED
AFTER POWER-UP TIME DELAY,
IN A NO FAULT CONDITION.
FAULT
NC
FIRE
NO
FAULT
NC
FIRE
NO
0 TO 1 MA
0 TO 1 MA
5
4
3
5
4
3
1
2
1
2
TB1
TB1
TB3
CURRENT
M
M
*
*
oi
TEST
+
–
oi
oi
+
–
+
–
A1491
510 OHM
1 WATT
Figure 15—Typical Multiple Unit Configuration with End of Line Capacitors