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trademark of the National Fire Protection Association.
®
Life Safety Code
is a registered trademark of the
National Fire Protection Association.
1.0 Overview
The D340 Air Duct Smoke Detector Housing is
designed to mount to the ducts of heating, ventilation,
and air-conditioning (HVAC) systems to monitor the
presence of smoke in the conditioned air.
Use the D340 with the D285DH Photoelectric Smoke
Detector (provided separately). The detector is
combined with an efficient housing design to sample
the air passing through a duct and detect potentially
hazardous conditions. When it detects smoke, the
detector sends an alarm signal to the control panel.
The control panel initiates the necessary action to shut
off fans and blowers or to switch to other air handling
systems.
The D340 operates on a two-wire loop, and requires a
smoke detector head.
Test the system by placing an external magnet on the
housing or switching the keyswitch from a Remote
Test station. Reset control requires a 24 V supply from
the control panel or an external power supply.
You can reset the detector by shutting down zone
power. If your system has a D344-RT Remote Test Kit,
you can reset the system using the keyswitch.
Install the D340 according to:
•NFPA 90A: Standard for the Installation of Air
Conditioning and Ventilating Systems
®
• NFPA 72: National Fire Alarm Code
• NFPA 101: Life Safety
Code®
• IBC: International Building Code
• IFC: International Fire Code
• Any applicable local and state codes
• Local authority having jurisdiction (AHJ)
2.0 D340 Options
Table 1: D340 Options
Options Description
D285DH Photoelectric smoke detector head
D344-1.5 1.5 ft (0.5 m) sample tube
D344-3 3 ft (1 m) sample tube
D344-5 5 ft (1.5 m) sample tube
D344-RT Remote Test Kit (D307)
D344-RL Remote LED Indicator Kit (D306)
D344-TF Tube filters for sample and exhaust tubes
(20 per package)
SMK-TM Test magnet
DRA-5 Remote alarm indicator
D275 End-of-line (EOL) module
3.0 Assembly
The D340 includes:
• One housing, power card, and cover assembly
• Two #10-24 x 1 in. machine screws for mounting
• Two #10-24 jack nuts
• One exhaust tube
• Two tube clamps with four screws
• Two foam gaskets
• Two air filters
• One drilling template
• One cover gasket
The D340P also includes a smoke detector head and
1.5 ft (0.5 m) tube.
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4.0 Sample Tubes
The sample tubes must extend across the width of the
duct. The three sizes of sample tubes are:
• D344-1.5 (1.5 ft [0.46 m])
• D344-3 (3 ft [0.91 m])
• D344-5 (5 ft [1.52 m])
Sample tubes include an end plug that must be
installed in the narrow end of the tube (Figure 1).
Figure 1: D344-1.5 Sample Tube
1
1 - Set screw 2 - End plug
You can combine or cut sample tubes to make
different lengths. A sample tube can be a maximum
length of
10 ft (3 m) or a minimum length of 1 ft (0.3 m). For
example, you can join a 3 ft (1 m) and a 5 ft (1.5 m) to
make an 8 ft (2.4 m) sample tube.
To combine sample tubes:
1. Remove the roll pin and set screw from one of the
sample tubes.
2. Remove the end plug from the other sample tube.
3. Push the flared end over the sample tube you want
to lengthen.
4. Align the holes, insert the set screw, and reinstall
the end plug. For example, if you want a 7 ft (2 m)
sample tube, combine a 3 ft (1 m) sample tube and
a 5 ft (1.5 m) sample tube. Then cut 1 ft (0.3 m)
from the narrow end to get the necessary length.
Sample tubes must have at least 12
sample holes within the duct. Do not cut
sample
tube to less than 12 sample holes.
2
D340 | Installation Guide | 4.0 Sample Tubes
Figure 2: Support Hole Position
1
1 - 1 in. to 2 in. (2.5 cm to 5 cm)
5. Seal the gap between duct and sample tube. You
can remove up to 6 in. (15 cm) from the D344-1.5
for 1 ft (0.3 m) duct installations.
When using the D344-1.5 in installations where the
duct width is between 12 in. (31 cm) and 18 in.
(46 cm), cover some of the sample holes. The
D344-1.5 has 19 sample holes, but only 12 are
required for normal installations. Depending on
the length, you might have to cover some of the
holes with duct tape. Use even spacing when
covering the sample holes to allow an even sample
across the width of the duct. Refer to Figure 3.
Figure 3: D344-1.5 Sample Tube
1
1 - Place tape over these sample holes
Sample tubes over 3 ft (1 m) must be supported at
the end opposite the duct detector. The support
hole should be 1 in. to 2 in. (2.5 cm to 5 cm) below
the entry hole to allow for possible moisture
drainage (Figure 2).
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D340 | Installation Guide | 5.0 Mounting
5.0 Mounting
5.1 Preparing the Duct
You must verify the duct air flow and velocity. The
D340 is designed for use in air handling systems with
air velocities between 300 ft/min and 4000 ft/min
(1.5 m/sec to 20.3 m/sec). Check the HVAC
engineering specifications to ensure the air velocity in
the duct falls within these parameters. If necessary, use
a velocity meter to check the air velocity in the duct.
5.1 Determining the Mounting Location
To obtain a representative air sample, avoid
stratification and dead air space. These conditions can
be caused by return duct openings, sharp turns,
connections, or long, uninterrupted runs. For this
reason, place the D340 in the range of six to ten times
the width of the duct from any uninterrupted run.
Refer to Figure 4 and Figure 5.
Figure 4: Typical D340 Placement – Example A
5.2 Positioning the D340
The D340 can be mounted in any direction of 90°
increments without regard to the air flow direction
(Figure 6).
Figure 6: D340 Positions
1
22
11
2
2
1
1
3
2
1 - Bend or other obstruction
2 - Six to ten times the width of the duct
3 - Width of duct
Figure 5: Typical D340 Placement – Example B
1
3
2
1 - Return air inlet
2 - Six to ten times the width of the duct
3 - Width of duct
11
22
3
1 - Air flow
2 - Correct mounting position
3 - Incorrect mounting position
1
3
1
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1. Locate the D340 mounting template (Figure 7) and
remove it from its backing.
Figure 7: D340 Mounting Template
5
2
1
DUCT SMOKE DETECTOR
MOUNTING TEMPLATE
REMOVEABLE AFTER DRILLIN G
6
D340 | Installation Guide | 5.0 Mounting
This attaches the jack nuts to the duct. You might
have to hold the jack nuts with a installer wrench
or a pair of pliers while tightening the screws to
stop the jack nut from spinning in the hole.
Remove the screws for later use.
7. Place the two foam gaskets over the sample and
exhaust ports on the back of the D340 (Figure 10).
Figure 10: Gasket Placement
3
4
4
1 - 16 in. (41 cm)
2 - 6.5 in. (16.5 cm)
3 - Two 1-3/4-in. (45-mm) diameter holes for the
sample tubes
4 - Two 3/8-in. (9.5-mm) diameter holes for
mounting to the duct
5 - 1.5 in. (38.1 mm)
6 - 8.0 in. (20.5 cm)
2. Place the template over the desired location on the
duct (Figure 8).
Figure 8: D340 Template Placement
16.070 in. (40.8 cm)
6.480 in. (16.5 cm)
(2) 1-3/4 in. (44.5 mm) DIA. HOLES FOR SAMPLING TUBES
(2) 3/8 in. (9.5 mm ) DIA. HOLES FOR DUCT MOUN TING
DUCT SMOKE DETECTOR
MOUNTING TEMPLATE
REMOVEABLE AFTER DRILL ING
1
1 - Foam gasket (2)
8. Mount the D340 to the jack nuts using the
supplied
10-24 x 1-in. machine screws (Figure 11).
Remember that overtightening the screws can
cause excessive bowing of duct.
Figure 11: Mounting the D340 to the Jack Nuts
3. Drill out the required holes and remove any
remaining debris.
4. Remove the template.
5. Place a #10-24 jack nut (Figure 9) in each of the
1 - Two 10-24 x 1-in. machine screws
9.Locate the wiring knockout holes (Figure 12).
1
3/8 in. (9.5 mm) holes.
Figure 9: Jack Nuts
6. Insert the #10-24 x 1 in. machine screws into the
jack nuts and firmly tighten.
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D340 | Installation Guide | 5.0 Mounting
Figure 12: Wiring Knockout Locations
1
2
1
1 - Wiring Knockouts (5) 2 - Earth ground screw
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10. Locate the sample and exhaust tubes (Figure 13).
Ensure the sample tube has a plug installed at the
narrow end of the assembly.
Figure 13: Exhaust and Sample Tubes
D340 | Installation Guide | 5.0 Mounting
13. Secure the tubes in place using the tube clamps
provided (Figure 16).
Figure 16: Sample and Exhaust Tubes in D340
1
2
4
3
1 - Exhaust tube
2 - Leave end open
3 - Sample tube
4 - Insert plug
11. Note the direction of the airflow in the duct. The
sampling holes in the sample tube must face into
the air flow (Figure 14). The exhaust tube must be
downwind from the sample tube (Figure 15).
Figure 14: Duct Air Flow
1
2
1
2
1 - Exhaust tube
2 - Sample tube
3
3 - D340
4 - Tube clamps (2)
4
14. Place the tube filters over the open ends of the
sample and exhaust tubes (Figure 17).
Figure 17: Tube Filters
1
2
3
4
1 - Air flow 2 - Sample holes
Figure 15: Exhaust Tube Position
1
3
2
1 - Air flow
2 - Sample tube
3 - Exhaust tube down stream from sample tube
12. Insert the sample and exhaust tubes into the D340,
ensuring the sample tube holes face into the air
flow. Ensure the tube alignment point set into the
D340.
1 - Exhaust tube
2 - Sample tube
NFPA-72 requires a semi-annual visual
inspection of detector housings. Clean or
replace the tube filters at this time. If
replacement filters are needed, order the
D344-TF.
3 - D340
4 - Tube filters (2)
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D340 | Installation Guide | 6.0 Selecting the Jumper
6.0 Selecting the Jumper
6.1 Location
Figure 18 shows the locations of the tamper and reset
jumpers on the power card.
Figure 18: Jumper Locations
1
BBR
2
LRE
KND
Tamper
Disable
14 13 12 11 10 9
1 - D340 Power card
3 - Reset jumper
2 - Tamper jumper
The Tamper Jumper (Figure 19) enables or disables the
housing cover Tamper Switch. When this jumper is
enabled, a trouble is indicated if the cover is removed.
Figure 19: Tamper Jumper
B
G
Y
O
L
R
E
R
U
N
L
N
Reset
Disable
3
1
2
3
4
5
6
7
8
Figure 20: Reset Jumper w/Remote Display
Units
1
2
1 - Disabled 2 - Enabled
Disable the Reset jumper whenever you are
not using the D344-RT (D307).
7.0 Wiring
7.1 Terminals
Figure 21: Terminal Wiring
(-)
2
34
OUTIN
1
(+)
14131211910
1
2
1 - Disabled 2 - Enabled
The Reset Jumper (Figure 20) enables or disables the
Remote Reset (keyswitch). The Power Off Reset from
the control panel zone functions normally regardless of
the jumper setting.
1 - Optional external power (24 VAC/VDC)
2 - Remote LED
3 - Loop (+)
4 - Loop (-)
7.2 Primary Power
The D340 is designed for a two-wire loop power
ranging from 8.5 VDC to 32 VDC. For Remote Test
or Remote LED, you must use an external 24
VDC/VAC that can supply a minimum of 170 mA.
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7.3 D340 Two-Wire D344-RT (D307)
D340 | Installation Guide | 7.0 Wiring
7.4 D344-RL Remote Indicator Plate
NFPA-72 requires that where in-duct
smoke detector housings are installed in
concealed locations more than 10 ft (3 m)
above the finished floor or in arrangements
where the detector’s alarm indicator is not
visible to responding personnel, the
detectors have remote alarm indicators.
Do not exceed 500 ft (152 m) between the
D344-RT (D307) Remote Test/Indicator
Plate and the D340. Use 18 AWG (1.2
mm) or larger wire.
Figure 22: D340 Two-wire to the D344-RT (D307)
Wiring
1
2
3
4
5
6
7
8
14 13 12 11 10 9
1
2
3
4
5
6
7
8
9
1 - Voltage in (+)
2 - Voltage out (-)
3 - Yellow LED
4 - Voltage monitor
5 - Ground (-)
1
2
3
4
5
6
7
8
6 - Remote test
7 - Green LED
8 - Red LED
9 - D340
10 - D307
1
2
6
4
5
8
3
7
10
Do not exceed a distance of 500 ft (150 m)
between the D344-RL (D306) Remote
Indicator Plate and the D340. Use 18
AWG (1.2 mm) or larger wire.
Verify the air flow to ensure the system is properly
operating. Use a manometer to verify the correct
velocity pressure readings ranging from 300 ft/min
to 4000 ft/min (1.5 m/sec to 20 m/sec).
The pressure differential between sampling tubes is
a minimum of 0.01 in. (0.25 mm) of water to a
maximum of 1.8 in. (45.7 mm) of water.
1. Check the wiring from the control panel to the
last duct detector on each run for proper
polarity and continuity.
2. Ensure each run terminates with an EOL
resistor as specified by the control panel
manufacturer.
3. Apply power to the system, and check for
alarms.
a. Note which smoke detectors are in alarm (if
any) and shut down the system.
b. Remove these detectors from their duct
housing and recheck the duct housing for
proper wiring. If the problems persist,
replace the affected smoke detectors or
swap them with known good units. This
determines if the problem is caused by the
detector or the duct housing.
c. If there is a system alarm with no detector
alarms present, remove all smoke detectors
and check the wiring at each duct housing.
Pay close attention to the wiring of each
EOL resistor.
4. When the system is free of alarms, check each
detector to ensure the red LED indicator flashes
approximately every 4 sec for the D285DH.
This verifies the detector is receiving power and
properly operating.
5. Test each detector to ensure it causes a control
panel alarm. Reset the control panel after each
test. Test the detectors by doing one of the
following:
a. Place an SMK-TM magnet against the duct
housing’s Test Point notch on the front
cover (Figure 27).
b. Switch a signal from a D344-RT (D307)
Remote Test Indicator Plate.
When a detector alarms, the red LED
indicator activates and latches to the ON
6. You can reset the detector by momentarily
position. Clear the alarm before proceeding
to the next detector.
removing power.
7. For duct detectors with the D307 Remote Test
Indicator installed, reset by moving the
keyswitch to the appropriate position and
observing the alarm LED.
Figure 27: Detector Testing
1
2
3
1 - D340 Duct Smoke Detector Housing
2 - Test point notch
3 - SMK-TM magnet
8. Check the overall loading of the alarm loop by
measuring the voltage across each EOL resistor.
This voltage should equal or exceed the
minimum specified by the control panel
manufacturer.
9.0 Maintenance
NFPA-72 requires a semi-annual visual
inspection of detector housings. Clean or
Clean the detector and base annually using a
vacuum or clean and dry compressed air.
replace the tube filters at this time. If
replacement filters are needed, order the
D344-TF.
Notify all concerned parties before and
after maintaining or testing the fire alarm
system.
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D340 | Installation Guide | 10.0 Specifications
.
10.0 Specifications
Table 2: D340 Specifications
Option Description Option Description
D275 End-of-line (EOL) module D344-RL Remote LED Indicator Kit (D306)
D285DH Photoelectric smoke detector head D344-TF Tube filters for sample and exhaust tubes (20 per package)
D344-1.5 1.5 ft (0.5 m) sample tube SMK-TM Test magnet
D344-3 3 ft (1 m) sample tube DRA-5 Remote alarm indicator
D344-5 5 ft (1.5 m) sample tube
D344-RT Remote Test Kit (D307)
Power Requirements
Operating Voltage
Maximum RMS
Ripple
Current Draw
Operating
Temperature
Humidity
Air Velocity
Weight:
Dimensions
(H x W x D)
Power-up Time
8.5 V to 32 V
Condition
Standby
Trouble
Alarm
Condition
Standby
Trouble
Alarm
Condition
Standby
Trouble
Alarm
8.5 VDC to 32 VDC from two-wire loop. Optional 24 VDC/VAC from control panel or external supply
25% of DC input
Dependent on the control panel that must limit the alarm current to 100 mA maximum.
+32°F to +120°F (0°C to +49°C). For UL listed requirements, the operating temperature range is
+32°F to +100°F (0°C to +37.8°C).
0% to 95% relative humidity
300 ft/min to 4000 ft/min (1.5 m/sec to 20.3 m/sec)
3.75 lbs. (1.7 kg)
6.5 in. x 15.5 in x 4.3 (16.5 cm x 39.5 cm x 11 cm)
22 sec maximum
D340 with D344-RT, D344-RL, and External Power
Loop Power
< 120 μA
< 170 μA 30 μA
Current limit to 100 mA
D340 with D344-RT, D344-RL without External Power
Loop Power
8.5 V to 32 V
< 140 μA
< 170 μA
Current limit to 100 mA
D340 without D344RT, D344RL without External Power
Loop Power
8.5 V to 32 V
< 130 μA
< 150 μA
Current limit to 100 mA
External Power
24 V
5 mA
170 mA in Remote Test
Bosch Security Systems, Inc. | 7/09 | F01U071685-06 13
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Bosch Security Systems, Inc.
130 Perinton Parkway
Fairport, NY 14450-9199
(800) 289-0096