Det-Tronics U7698A, B, C, E Unitized Frequency IR Detector/Controller - Manual (Page 12)

CAUTION
Any extinguishing equipment connected to the sys-
tem must be disabled when the system is tested to
prevent unwanted actuation of this equipment.
To test the system, point a flickering IR source at each
unit or activate the
oi test for five to ten seconds. Alarm
response indicates that the viewing window is clean and
that all electronic circuitry is operational. Lack of
response may indicate reduced sensitivity due to con-
tamination on the viewing window, a damaged sensor, or
electronic circuitr y problems. Refer to the
“Troubleshooting” section of this manual if the detector
does not respond properly.
MAINTENANCE
The detector requires no periodic calibration. However,
to maintain maximum sensitivity, the viewing window
must be kept clean at all times. The length of time
between periodic cleanings will be determined by the
nature and amount of contaminants present in the envi-
ronment.
Remove the oi ring from the detector and clean the
viewing window thoroughly, all the way to the edge. Also
clean the back side of the
oi ring. When re-installing the
reflective oi ring, hold it by its tabs to avoid leaving fin-
gerprints on the reflective surface. Re-install the ring so
that the opening is positioned directly opposite the
oi
test lamps on the detector. The opening should be
pointed down to prevent a buildup of contaminants. If
corrosive contaminants in the atmosphere cause the
reflective rings to deteriorate to the extent that it is no
longer possible to restore them to their original condition,
they must be replaced.
To clean the window use a clean cloth or tissue and Det-
Tronics window cleaning solution (part number 001680-
001).
NOTE
Remove input power when cleaning the detector
windows to prevent unwanted output activation.
Rubber O-rings are used to ensure the watertight integri-
ty of the detector housing. Periodically, the housings
should be opened and the O-rings inspected for breaks,
cracks, or dryness. To test the O-rings, remove them
from the detector housing and stretch them slightly. If
cracks are visible, they should be replaced. If they feel
dry to the touch, a thin coating of lubricant should be
applied. When re-installing the O-rings, be sure that
they are properly seated in the groove on the housing. It
is imperative that these O-rings be properly installed and
in good condition. Failure to properly maintain the O-
rings can allow water to enter the detector and cause
premature failure. The life expectancy of rubber O-rings
can vary considerably, depending on the amount and
nature of contaminants that are present in the environ-
ment.
A coating of lubricant should also be applied to the
threads on the detector enclosure before re-assembling
the detector. This will both lubricate the threads and
help to prevent moisture from entering the detector
housing.
TROUBLESHOOTING
Before disassembling the unit, perform the following
steps.
1. Disable any extinguishing equipment that is con-
nected to the unit.
2. Inspect the viewing window for contamination. The
infrared detector is relatively insensitive to airborne
contaminants, however, thick deposits of ice, dirt, or
oil will reduce sensitivity. To clean the window, use
Det-Tronics window cleaner (part number 001680-
001) and a soft cloth or tissue. (Refer to the
“Maintenance” section of this manual for complete
information regarding cleaning of the detector view-
ing window.)
3. Check input power to the unit.
4. Hold a flickering IR source close to the detector or
press the
oi test button for five to ten seconds. The
alarm relay will energize and the LEDs will turn on.
5. Remove the IR source (or release the oi test button).
The alarm relay will become de-energized and the
LEDs will turn off if non-latching operation is select-
ed.
6. If the device did not respond properly, check the oi
lamps to be sure that they flash during the oi test
and also check the oi ring for proper alignment.
Turn off the input power to the system and check all
wiring for continuity.
7. If the wiring checks out, replace the IR module.
a. Remove the sensor housing (see Figure 6).
CAUTION
Do not open the detector/controller housing in a
hazardous area without first removing power,
including power to the relay contacts.
b. Remove the connector plug from the IR mod-
ule.
c. Unplug the IR module from the bulkhead.
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