Det-Tronics U7602B-P Unitized UV Flame Detector/Controller - Manual (Page 8)

CONE OF VISION—
The U7602 detector has a nominal 90 degree cone of
vision, with the highest sensitivity lying along its cen-
tral axis, as shown in Figure 5.
SYSTEM SENSITIVITY—
The U7602 Detector/Controller is set at the factory for
25 cps (counts per second). Other sensitivity settings
are available as an option. When the sensitivity is set
at 25 cps, the U7602 can respond to a gasoline flame
with a one-square-foot burning surface area (0.09
square meter) at a distance of 35 feet (10.7 meters).
RESPONSE TIME—
The response time of the detector is a function of fuel,
fire size, distance, orientation of the fire source, alarm
threshold (cps) setting and the field adjustable time
delay setting. Response times to an intense fire sig-
nal are field adjustable from 0.025 to 30 seconds.
INPUT VOLTAGE—
Models available:
12 vdc (10.5 to 16 vdc)
24 vdc (18.0 to 38.0 vdc)
120 vac, 50/60 Hz (Accepts fluctuations between 85
and 110 percent of voltage rating.)
220/240 vac, 50/60 Hz (Accepts fluctuations between
85 and 110 percent of voltage rating.)
RELAY CONTACT RATINGS—
Form A (normally open), 0.2 ampere maximum at 50
vdc. Optional form C (normally open and normally
closed), 3 amperes maximum at 30 vdc or 120 vac.
WIRING REQUIREMENTS—
From three to nine wires are required depending on
the capability of the external control system, as shown
in Figure 6. Wires must be 22 gauge minimum. If
used, the current signal output line must be a sepa-
rate, shielded wire.
TEMPERATURE RATING—
Operating:
–40°F to +167°F (–40°C to +75°C).
Storage: –67°F to +185°F (–55°C to +85°C).
HUMIDITY—
0 to 95% relative humidity.
DIMENSIONS—
Refer to Figure 7.
SHIPPING WEIGHT—
Aluminum enclosure: 2.0 kilograms (4 1/2 pounds).
Stainless steel enclosure: 3.15 kilograms (7 pounds).
CURRENT OUTPUT—
From 0 to 400 microamperes (standard).
4 to 20 ma output (optional).
5 95-8239
0 °
15 °
30 °
45 °
15 °
30 °
45 °
VIEWING ANGLE
A1288
100
90
80
70
60
50
40
30
20
10
DETECTION
DISTANCE
(PERCENT)
100% REPRESENTS THE MAXIMUM DETECTION DISTANCE FOR A
GIVEN FIRE. THE SENSITIVITY INCREASES AS THE ANGLE OF
INCIDENCE DECREASES.
CONTROLLER
UV
SENSOR
TUBE
INPUT POWER
}
FAULT RELAY
*
FIRE RELAY
SIGNAL RETURN LINE
CURRENT SIGNAL OUTPUT LINE
oi TEST LEAD
*
FAULT RELAY SHOWN ENERGIZED (NO TROUBLE IN CIRCUIT)
U7602
B208
Table 2—Current Signal Output Levels
Figure 5—U7602 Cone of Vision
Figure 6—Standard U7602 Detector/Controller System
* ±5%
Standard Optional
Current 4 to 20 ma
Signal Output Type of Fault
(µa) (ma) *
0 0 Open or shorted signal output line, or
loss of power to U7602
40 4 Normal operation
80 6 Dirty windows and/or oi reflector ring
— detector tube circuit not
functioning — low detector sensitivity
120 8 Some background UV present,
spurious detector discharges – high
detector sensitivity
160 10 High voltage fault (power monitor)
320 Over 19 Fire indication
Over 400 Over current