Installation Instructions

3Bosch | 6/04 | 49323C
3.0 Mounting
1. Before mounting, remove the dust cover from the
detector.
2. Mount the duct housing according to the
manufacturer’s instructions.
3. Mount the detector on the base by turning it
clockwise until it clicks into place (Figure 1).
The D285DH is keyed. Do not force a
detector onto its base.
4.0 Testing
1. Check the wiring from the control panel to the last
head on each run for proper polarity and continuity.
Ensure each run terminates with an EOL resistor as
specified by the control panel manufacturer.
2. Apply power to the system. Check for alarms and
troubles.
a. Note which detectors are in alarm (if any) and
shut down the system.
b. Remove these detectors from their bases and
recheck the bases for proper wiring. If the
problems persist, replace the affected
detectors or swap them with known good
units. This determines if the problem is
caused by the detector or the base.
c. In a system alarm with no detector alarms,
remove all detectors and check the wiring at
each base. Pay close attention to the wiring of
each EOL resistor.
D285DH | Installation Instructions | 3.0 Mounting
Figure 1: Mounting the Base
1 - Base contacts (three sets)
2 - Start the detector contacts at these three places
and rotate the base clockwise.
+1
R2
3-
1
2
1
2
2
1
3. When the system is free of alarms, check each
detector to ensure the red LED head indicator
flashes approximately every 4 sec. This verifies the
detector is receiving power and operating properly.
4. Test each detector to ensure it will cause a control
panel alarm. This is the only way to ensure proper
operation. Alarm the detector in on of the following
methods:
a. If the duct housing cover is in position, place
a magnet horizontally against the recess in
the cover to activate an internal reed switch.
b. With duct housing cover removed, use a UL
Listed aerosol smoke detector tester, such as
the Home Safeguard Industries’ 25S to
simulate an alarm. Follow the aerosol smoke
detector tester manufacturer’s instructions.
When a detector alarms, the red LED head
indicator activates and latches in the ON
position. Clear the alarm before proceeding
to the next detector.
5. Check the overall alarm loop loading by measuring
the voltage across each EOL resistor. The voltage
should equal or exceed the minimum specified by
the control panel’s manufacturer.