Installation Instructions
DS240 and DS241
Long Range Beam Smoke Detectors
1.0
Description
The DS240 and DS241 are long range projected beam type smoke detectors which consist of a separate transmitter and receiver. Internal pointability provides coverage flexibility without the need for brackets.
Automatic Signal Synchronization and Range Adjustment reduce installation costs. Selectable sensitivity and alarm response time provide installation flexibility.
• Listings and
Approvals:
UL
ULC
S3019
CS692
MSFM Permit #1943
NY City MEA Acceptance #MEA274-93-E
CSFM
FM
#7260-1062:106
Job #OX2A9.AY
• Standard
Accessories:
DIS2000 Remote Test/Indicator Plate and
• Options:
Test Cable
DIS240 Remote Indicator Plate, TK240
Field Test Kit, AL240 Alignment Light, and
TC2000 Test Cord.
2.0
Specifications
• Operating Voltage: DS240: 18.0 VDC to 32.0 VDC
DS241: 10.2 VDC to 15.0 VDC
• Standby Current:
DS240: Receiver: 45 mA @ 24.0 VDC
Transmitter: 20 mA @ 24.0 VDC
DS241: Receiver: 50 mA @ 12.0 VDC
Transmitter: 20 mA @ 12.0 VDC
• Receiver Alarm
Current:
DS240: 60 mA @ 24.0 VDC
DS241: 75 mA @ 12.0 VDC
• Range (distance between transmitter and receiver): 30 ft to 350 ft (9 m to 107 m)
• Spacing (distance between systems): Allow no more than 60 ft (18 m) between
• Pointability: systems. Sixty foot spacing is confirmed by Underwriters Laboratories, Inc. testing.
Internally pointable optics for ±90°
• Sensitivity:
• Alarm Contacts:
horizontal, and ±10° vertical adjustment.
Field selectable for 20, 30, 40, 50, 60, or
70 percent beam obscuration.
Normally Open contacts rated 1 A,
60 VDC maximum for DC resistive loads.
Do not use with capacitive or inductive loads.
• Trouble Contacts:
Normally Closed contacts rated 1 A, 60 VDC maximum for DC resistive loads. Do not use with capacitive or inductive loads.
• Aux. Alarm
Contacts:
Form "C" (NO, C, NC) contacts rated 1 A,
60 VDC maximum for DC resistive loads.
Do not use with capacitive or inductive loads.
• Tamper:
• System Signaling:
Conventional 4-wire system. Not for use with systems that incorporate an alarm
• Signal Delay:
verification feature.
Fire:
Selectable 30 sec or 5 sec
Trouble: 20 ± 2 sec
• Temperature:
Receiver: Access door tamper switch in series with trouble contacts.
Transmitter: Upon cover’s removal, cover tamper switch interrupts transmission.
• Mounting:
The storage and operating temperature range is -22°F to +130°F (-30°C to +54°C).
For UL Listed installations, the range is
+32°F to +130°F (0°C to +54°C).
The units are designed to be mounted to
4 in. (10 cm) square or octagonal electrical boxes (not supplied).
3.0
Principle of Operation
Each DS240 or DS241 beam smoke detector has a separate transmitter and receiver. The transmitter transmits an invisible infrared beam of a specific frequency and intensity. The receiver detects, then measures the beam’s intensity (see Figure 1).
Figure 1 - Infrared Transmission
As the beam is obscured by smoke, the receiver senses a decrease in the signal strength and measures that decrease. The receiver compares the signal level with two preset thresholds: an alarm threshold which is set using the sensitivity switch and a trouble threshold which is preset at approximately 10%. If the signal falls below the alarm threshold for the programmed alarm period, the receiver signals an alarm (see Figure 2).
Figure 2 - Beam Obscuration
If the signal falls below the trouble threshold for more than 20 sec, such as might happen if the beam is blocked by a foreign object, the receiver signals a trouble condition (see Figure 3).
Figure 3 - Beam Blockage
The receiver automatically compensates for the gradual loss of signal due to dust/dirt build-up on the cover. After 50 percent of the signal is lost, the receiver will indicate a trouble. When the dust/dirt build-up is cleaned or the blockage is removed, the detector automatically goes back to its normal operation level.
A trouble will be indicated at the receiver if the beam strength is increased by more than 20% for greater than 20 sec. Causes include improper initial alignment or the removal of a partial beam blockage at the time of alignment. Preform a fine-tune alignment (see Section
7.3 Fine Tune Alignment on page 6).
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4.0
Installation Considerations
The proper location and spacing of detectors is critical in a properly installed and operating fire alarm system. For best results, it is recommended that the detectors be located and spaced in accordance with the National Fire Protection Association (NFPA)
Standard 72 "The National Fire Code.” This standard is available at a nominal cost from The National Fire Protection Association,
Batterymarch Park, Quincy, MA, 02269.
In all installations, good engineering judgement should prevail. The following are some general considerations:
• Do not use mirrors. The detectors should be installed with a clear line-of-sight between the transmitter and receiver.
• The beam path should be clear of moving objects.
• Set the sensitivity based on the distance between the transmitter and receiver. See Section 7.2 Sensitivity Adjustment on page 5.
• The detectors may be mounted directly to the ceiling or to side walls. Do not mount the units where the beam path may run parallel within 4 in. (10.2 cm) of a corner.
• For a sloped or peaked ceiling, the beam path should be located within 3 ft (1 m) of the ceiling’s peak.
4.2 Avoid sources of bright light
Sunlight and light from extremely bright sources such as the exposed bulbs of high pressure sodium, mercury vapor, and metal halide lights can cause stray signals. The receiver should not be pointed toward any of these sources.
Sunlight: Avoid pointing the receiver directly at the rising or setting sun. If you are installing the unit where sunlight can’t be avoided, mount the receiver slightly higher than the transmitter and aimed down toward the transmitter. This should reduce this problem by causing the receiver to look below the horizon.
Bright Lights: Don’t mount the receiver where it is looking at exposed bulbs of high pressure sodium, mercury vapor, and metal halide lights. The illustration below shows where these exposed lights should be avoided.
Keep bright lights out of this area
4.5 ft. (1.4 m)
Receiver 14.5 ft.
(4.4 m)
225 ft. (68.6 m)
350 ft. (106.8 m)
Bare fluorescent lights may also pose a problem especially in long hallways where a series of lights run perpendicular to the beam.
Incandescent lights are not a problem as long as they are not directly in the beam path.
4.3 Use the correct wire gauge and length
• Stratification of air may hinder smoke from reaching detectors mounted close to the ceiling. Stratification occurs when smoke, rising because it is warmer than the surrounding air, reaches a level where it is the same temperature as the surrounding air and will not rise to the ceiling. If stratification is considered a possibility, extra beams should be installed where stratification is expected.
Beam smoke detectors are often used to protect very large areas.
This means that the wire runs used to power the detectors and signal alarm conditions can be very long. The voltage available at the end of very long wire runs may not be sufficient to power the detector, especially when the system is running on battery backup. It is very important that the correct wire gauge is used for these installations.
• Avoid areas subject to normal smoke concentrations such as kitchens and garages.
Use the following chart to determine the proper wire size, wire length and the number of transmitter and receiver pairs that can be used.
• Do not install units where normal ambient temperatures are below -22°F (-30°C) or above +130°F (+54°C).
The following are some specific installation considerations:
4.1 Avoid Sources of Heat and Air Movement
The detectors should be located where the beam path will not pass near heating and cooling outlets.
• Don’t mount where hot or cold air can blow directly into the beam path.
W i r e
L e n g t h
5 0 0
1 0 0 0 f t ( 1 5 2 f t ( 3 0 4 m ) m )
2
5
5
0
0
0
0
0 f t ( 7 6 2 f t ( 1 5 2 4 m ) m )
1 4 A W G
( 1 .
8 m m )
1 6
( 1 .
5
A W G m m )
1 8
( 1 .
2
A W G m m )
2 0
1 0
4
2 p p a i a i r s r p a i r s p a i r s s
W i r e S i z e
1 3 p a i r s
6
3 p p a i a i r s r s
1 p a i r
8
4 p p a i a i r s r s
2
1 p a i r s p a i r
• Heating, ventilating, and air conditioning systems can cause smoke to be blown away from the beam path.
- Smoke must accumulate in the beam path to be detected.
• Heaters mounted close to the beam path can cause the beam to become distorted.
You can test for beam distortion by monitoring the signal voltage.
After setup, the signal voltage of the detector should read 4 VDC.
Monitor the voltage and turn on all heating and cooling devices in the area. The signal voltage should not fluctuate more than 0.20 VDC. If it does, the detector should be moved to avoid these disturbances.
Page 2 P/N: 22066P © 2004 Bosch DS240/DS241 Installation Instructions
4.4 Provide a stable mounting surface
4.6 Consider the expected Fire load
Beam smoke detectors depend on the measurement of the projected beam to sense smoke. Therefore, shifts in the alignment of the beam due to movement of the transmitter/receiver can cause trouble or alarm conditions.
• Always select a stable mounting surface.
When designing a fire alarm system, consider the expected fire load within the application.
For instance, fires caused by the ignition of flammable petroleumbased liquids usually result in a rapid buildup of heavy smoke. When these types of fires are probable, use sensitivity settings 0 or 1 which provide a response time of 5 sec.
• Never mount the unit to a suspended support such as a pipe or length of wood supported at only one end.
5.0
Mounting
This type of mounting can create a “pendulum effect” which greatly multiplies even very small movements at one end of the support. For example, a 2 in. (5.1 cm) movement translates into a beam misalignment of over 20 ft at 350 ft (6 m at 107 m).
NOTE: This product is not designed for use in outdoor applications.
Install a 4 in. (10 cm) square or octagonal electrical box (not supplied) to a rigid surface that will not be subject to movement or vibrations.
Mounting surfaces should be supported at opposite corners to reduce the pendulum effect.
• Always select surfaces not subject to building movement.
NOTE: If not mounting to an electrical box, be sure the surface will not be subject to movement or vibrations. For example: do not mount directly to a suspended ceiling without extra support.
The automatic compensation circuits of the DS240 and DS241 will eliminate most problems created by normal building expansions
and contractions. In some unusual circumstances, the walls and support structure may be subject to more significant movement due to the operation of heavy equipment, such as cranes, anchored to the top of the walls.
• Remove the receiver's access door (1 screw), then remove the cover (4 screws). See Figure 4.
COVER MOUNTING
SCREWS (4)
When in doubt about mounting surface stability, measure the signal voltage of the detector. This voltage should be 4.0 VDC. Misalignment of the beam can cause this voltage to increase or decrease. The detector will indicate a trouble condition when the voltage increases to more than 4.8 VDC, or when it decreases to less than 2.0 VDC over a long period of time or to 0.4 VDC greater than 20 sec. For more information on reading this voltage, see Section 8.3 Reference
Voltage Calibration on page 6).
If movement of the mounting surface is suspected, relocate the detector to a surface that does not move or add supports to the mounting surface to prohibit movement.
ACCESS DOOR
Figure 4 - Access Door and Cover
• Remove the receiver’s backplate by removing the single mounting screw from the top of the circuit board carrier plate then separating the two plates (see Figure 5).
• DO NOT over-tighten the mounting screws.
REMOVE TO
EXPOSE BACKPLATE
When the detector is mounted to an electrical mounting box
[4 in. (10 cm) square or octagonal], the mounting plate may bow as a result of the mounting box screw tabs being below flush with the top edges of the mounting box. Over-tightening the mounting screws bows the mounting plate inward at the bottom, causing the optics to aim low.
Irregularities in the flatness of the mounting box edge surfaces or screw tabs will worsen this condition. Using only mounting boxes with flat, regular surfaces and properly formed screw tabs, and tightening the mounting screws to secure the mounting plate to
2 in./lb torque will minimize any misalignment caused by bowing of the mounting plate.
DO NOT
REMOVE
MOUNTING
SLOTS (4)
WIRING
ENTRANCE
Figure 5 - Removing the Backplate
• Bring wiring from the electrical box through the wire entrance.
NOTE: All wiring should be unpowered.
4.5 Consider the effects of stratification in cold environments
In very cold environments such as unheated warehouses, smoke may cool very quickly and is less likely to rise to the ceiling. Consider additional units at lower mounting heights to help compensate for this situation.
• Securely mount the backplate to the electrical box.
• Return the circuit carrier plate to the backplate. Secure it in place with the single mounting screw.
• Repeat this mounting procedure for the transmitter.
DS240/DS241 Installation Instructions © 2004 Bosch P/N: 22066P Page 3
6.0
WIRING
Only apply power after all connections have been made and inspected.
• Slide the Remote Indicator Connector over the pins just to the right of the receiver’s terminal strip.
CAUTION
• Wire the transmitter and receiver terminals as follows (see
Figure 6).
NOTE: Do not install on verified fire circuits.
AUX.
RELAY
ALARM
Receiver
FIRE
ALARM
TRBL
ALARM
VDC
1 2 3 4 5 6 7
– +
8 9
DS240/DS241 Receiver
Fire
Alarm
Trouble
Alarm
10 to 32
VDC
4 5 6 7
– +
8 9
Remote Indicator
Plate Connector
Alarm Loop
Fire Alarm
Control Panel
Power Loop –
Power Loop +
End of Line resistor
1 2
–
+
Transmitter
Figure 6 - Wiring a Single Unit
Fire Alarm
Control Panel
Alarm Loop
Power Loop –
Power Loop +
EOL
NOTE: Do not coil excess wiring inside the units.
DIS2000
Voltage Monitor
Ground (–)
Red LED
Yellow LED
Green LED
Violet
Black
Red
Yellow
Green
• Transmitter Terminals 1 & 2:
Input power terminals. See Section 2.0 Specifications on page 1 for the operating voltages of the DS240 and DS241.
• Receiver Terminals 1, 2 & 3:
Form "C" Auxiliary relay contacts. Terminals 1 & 2 will open on fire alarm; Terminals 2 & 3 will close (short) on fire alarm.
Figure 7 - Connecting the DIS2000 Remote Indicator Plate
NOTE: If connecting a DIS240 Remote Test/Indicator Plate, consult the
DIS240 Installation Instructions (P/N: 24171).
• Receiver Terminals 4 & 5:
Normally Open Fire alarm contacts will close (short) on fire alarm.
7.0
SET-UP
• Receiver Terminals 6 & 7:
Normally Closed Trouble contacts will open for trouble alarm.
Before starting this section, confirm that all connections have been made and are secure, then apply power to both units.
• Receiver Terminals 8 & 9:
Input power terminals. See Section 2.0 Specifications on page 1 for the operating voltages of the DS240 and DS241.
• Press the Aim Mode button (directly above the green LED) on the transmitter (see Figure 8). This allows the transmitter to power up while its cover is off.
AIM MODE
BUTTON
NOTE: Resetting from a fire alarm requires power to the receiver to be interrupted for at least one second. If not provided by the fire panel, it can be accomplished by installing a switch in series with Terminal 9.
Remote Indicator Plate
The DIS2000 Remote Indicator Plate is shipped with the DS240/
DS241 as a standard accessory. Although the Remote Indicator Plate is not required, the manufacturer recommends its installation to provide a means of checking the condition of the detector from ground level.
GREEN
LED
Figure 8 - Cutout View of Transmitter Circuit Board Showing
If a DIS2000 or DIS240 Remote Indicator Plate will be used, install the Remote Indicator Connector to the receiver now (see Figure 7).
Aim Mode Button Location
- Check the transmitter’s green LED. It should be flashing on and off.
NOTE: The DIS240 remote indicator should be located no further than 100 ft (31 m) from the receiver and wired with 18 AWG
(1.2 mm) or larger wire. The DIS2000 may be wired up to
500 ft (152 m) from the receiver.
Page 4 P/N: 22066P © 2004 Bosch DS240/DS241 Installation Instructions
- If the LED is off, check for the presence of power and proper polarity on Terminals 1 (–) & 2 (+).
• Replace and secure the transmitter's cover when this alignment procedure is complete.
• Check the transmitter's green LED. It should be flashing.
- A steady green LED indicates a faulty transmitter, and the unit should be returned to the factory.
• Check the three receiver LEDs (see Figure 9).
Red/Alarm
Trouble/Yellow
Green/Normal
• Replace and secure the transmitter's access door.
• Align the receiver to the image of the transmitter using the above preliminary alignment procedure.
Figure 9 - Receiver's LEDs
- It is normal for all of them to be on at this time, with the green indicator either flashing or constantly on.
• Check the receiver's green LED. It should be flashing. This indicates that the preliminary alignment is complete.
- If all are off, check for the presence of power and proper polarity on Terminals 8 (–) & 9 (+).
- If the receiver’s green LED is not flashing, repeat the preliminary alignment procedure for the receiver.
7.2 Sensitivity Adjustment
• Mount an AL240 strobe aiming light or equivalent (such as a
Faraday 5508) as close to the receiver as possible (preferably on top of the receiver).
Front Bore Sight
Rear Bore Sights
Use the chart below ( Figure 12) to aid in the sensitivity adjustment.
- Point it at the transmitter as your guide for aiming (an aiming light may not be necessary for short distance separations).
7.1 Preliminary Alignment
Each optical module is equipped with two alignment mirrors (one on each side) for initial alignment (see Figure 10).
FRONT VIEW SIDE VIEW
VERTICAL
FINE TUNE
HORIZONTAL
FINE TUNE
5
6
7
2
3
4
S w i t c h
S e t t i n g
R e c o m m e n d e d S e t t i n g s
S e n s i t i v i t y
A l a r m
R e s p o n s e
B e a m L e n g t h
0
1
3 0 %
6 0 %
5 s e c
5 s e c
3 0 1 0 0 f t ( 9 3 1 m )
1 0 0 3 5 0 f t .
3 1 1 0 7 m )
2
3
4
5
6
7
0
0
0
0 %
0 %
0
%
%
%
%
3
3
3
3
3
3
0
0
0
0
0
0 s s s s s s e e e e c c c e c e c c 1
3
4
7 0
9 0
6 0
0
5 -
1 2 0
-
3
5 0
7 5
1 0 0
1 4 0
1 8 0
5 0 f f f f f t .
t t f t t .
t
(
(
9
1
( 2
2
( 3
-
4 -
7 -
4 9
1 5
2 3
1 3 1
4 3
1 m
7 5 5 m
0 7
) m m
) m
)
) m
)
)
ALIGNMENT
MIRRORS
FRONT BORE SIGHT
REAR BORE SIGHTS
ALIGNMENT
MIRROR
Figure 10 - The Optical Module
To initially align an optical module, look into either mirror from a side angle at least 2 ft (61 cm) from the module. The optical module is pointed at objects seen in the mirror when the orange colored front bore sight is in the center of the rear bore sights (see Figure 11).
Figure 12 - Recommended Settings Chart
NOTE: Positions 8 and 9 are not valid positions. They are not to be used.
• Select the appropriate sensitivity setting from the above chart based on the distance between the transmitter and receiver.
• Set the receiver’s Sensitivity switch at this setting.
Figure 11 - View of the Alignment Mirror with Bore Sights Aligned Properly.
HINT: Use alignment sights like aiming a gun.
• Rotate the transmitter's optical module left or right until the image of the aiming light (or receiver image, if aiming light is not used) can be seen in the mirror.
• The Sensitivity switch is located just to the right of the optical module on the receiver. The indicator or pointer marking runs along the side of the switches' shaft (see Figure 13).
0
Figure 13 - Sensitivity Switch
- If initially aimed too high or low, adjust the Vertical Fine Tuning adjustment allen screw (with supplied allen wrench) slightly up or down until the image is found.
• Use the Vertical Fine Tuning adjustment screw and the
Horizontal Fine Tuning adjustment screw to fine tune the image to the center of the mirror (in-line with the front and rear bore sights).
• The recommended settings chart lists distances with some settings that overlap. For more sensitive detection, select the lower number setting. For better immunity to false alarms, select the higher number setting.
DS240/DS241 Installation Instructions © 2004 Bosch P/N: 22066P Page 5
7.3 Fine Tune Alignment
• Connect the supplied TC2000 Test Cable to Pins 1, 2 and 3 of
P6, the group of pins located just to the right of the receiver’s terminal strip (see Figure 14).
• An alarm test may be performed here if desired by connecting the white and black wires of the TC2000. To reset the unit, temporarily remove power.
• Press the receiver’s Set-up button located just below the P6/test cable connection (see Figure 15). Press only if the covers are
on both transmitter and receiver.
- This starts a one to two minute automatic internal setup process that results in a reference voltage for measuring beam blockages.
LEDs
Setup
Button
Figure 14 - TC2000 Connection
- Temporarily disconnect the Remote Indicator Plate connector, if installed.
Figure 15 - The Receiver's Set-up Button
• Connect a 20,000 Ohm/volt (or greater) DC VOM to the black
(–) and red (+) leads of the TC2000.
- The red and yellow LEDs should turn off, and the green LED will turn on steady. After some voltage fluctuations, the meter should settle at 5.0 VDC.
- Set meter scale so that readings of 0.0 to 5.0 VDC can be read.
NOTE: Be careful not to block the beam or move the units during this time.
• Check the three LEDs on the receiver.
- If the beam is being received by the receiver, the green LED should be flashing, and the red and yellow LEDs should be on steady.
- If the green LED is on steady, the beam is not reaching the receiver. If this is the case, the preliminary alignment procedure should be attempted again.
• Observe the meter readings and adjust the receiver’s optical module using the Horizontal and Vertical Fine Tuning adjustment screws for a maximum reading on the meter. This is the most
critical process of alignment. For the most effective operation of this system, the peak voltage during fine tune alignment must be obtained.
• If the voltage is not between 3.8 VDC and 4.2 VDC, push the Setup button again.
• After set-up is complete, remove the test cable (and reconnect the Remote Indicator Plate connector if used).
• Replace and secure the access door.
8.0
Other Information
8.1 Fire Alarm Reset
NOTE: When performing fine tune alignment, keep arms and hands
Hint:
away from the front of the receiver and out of the beam path.
Make a note of the alignment voltage. It may be helpful if future troubleshooting is necessary.
• After completing the fine tune alignment, remove the test cable, then replace and secure the receiver's cover.
To reset the receiver after a fire alarm has occurred, remove power from the receiver for at least one second, then re-apply (see also,
Section 8.4 Power Outage on page 7).
• The maximum voltage peaked reading will vary depending on the distance between the transmitter and receiver. The acceptable peaked voltage range is 0.50 to 5.00 V. The voltage at the receiver is greater at shorter distances. It is very important to peak the voltage to insure a stable trouble free detector.
8.2 Cleaning
At least once a year, the outside of the covers should be cleaned with a common window cleaner and a soft, clean cloth. Under normal conditions, this should not result in a trouble alarm as long as the beam is not continuously blocked for more than 18 sec. After cleaning, recheck the reference voltage. If the voltage is less than 3.8 VDC, or greater than 4.2 VDC, calibrate the units (see Section 8.3 Reference
Voltage Calibration).
8.3 Reference Voltage Calibration
• Check the status of the receiver’s green LED. It should still be flashing.
- At the end of the setup period, the receiver’s green LED will flash, and the voltage will drop to between 3.8 and 4.2 VDC.
This is a reference voltage that later readings can be compared to when determining the need for cleaning.
• With the meter still connected to the test cable, re-install the test cable to P6 through the opening in the cover (red lead towards center of unit).
The reference voltage of the detectors should be checked at least once a year (or more often if required by local regulations or authorities having jurisdiction). Clean covers are necessary for proper
reference voltage readings.
Page 6 P/N: 22066P © 2004 Bosch DS240/DS241 Installation Instructions
To check the reference voltage, remove the receiver's access door and measure the reference voltage, using the supplied test cable, or measure the voltage at the DIS240 Remote Indicator Plate (if used).
If the voltage is less than 3.8 VDC, remove the cover and perform a fine tune alignment including use of the Set-up switch. If above 4.2
VDC, press the Set-up button. Calibration is not necessary if the voltage is between 3.8 VDC and 4.2 VDC.
4.0
3.5
3.0
2.5
8.4 Power Outage
When power is removed, then reapplied to the receiver (such as in a power outage or alarm reset), the original reference voltage information is lost.
If the cover is on at the time of power-up, the receiver will automatically restart the internal set-up process (to get a new reference voltage) when power is applied. If the cover is off, the Set-up button will have to be pressed after the cover is reattached.
2.0
1.5
UL Minimum Sensitivity
1.0
0.5
30% 40% 50%
20%
60% 70%
0.0
UL Maximum Sensitivity
30 (9m)
80 (24m) 130 (40m) 180 (56m)
230 (70m)
Distance Between Transmitter and Receiver
280 (85m) 330 (100m)
8.5 Remote Indicator Plate Connector
Momentarily connecting the orange and black leads of the connector
(see
Figure 16) will produce a test alarm. For a remote test, install a momentary switch between the orange and black wires.
ORANGE - Remote Alarm Test
BLUE - Analog ref. voltage out
BLACK - Common (-)
RED - Red LED indicator
YELLOW - Yellow LED indicator
GREEN - Green LED indicator
Figure 16 - Remote Indicator Plate Connector
The black and blue wires may be connected to an analog meter for reference voltage measurements. The red, yellow, and green wires may be connected to remote LEDs.
Figure 17 - Smoke Density/Obscuration Chart
The next chart (
Figure 18) shows the Sensitivity Pot Setting (total obscuration) that is needed for alarm.
S e
S n s i t
0
P e t t o
2 o
4
5
1 o r
7 r
i t i n v i
3
6
g t y T o t a l
O b s c u r a t i o n a t A l a r m
2 0 %
3 0 %
4 0 %
5
6
7
0
0
0
%
%
%
Each wire is current limited to a maximum of 10.0 mA DC.
8.6 Smoke Density/Obscuration Information
Figure 18 - Sensitivity Pot/Obscuration Chart
8.7 Field Sensitivity Measurements
The total obscuration of the infrared beam is dependent upon the density and width of the smoke cloud along the beam path. As the width of the smoke cloud increases along the beam path, less dense smoke will be needed for an equal obscuration of the beam path. In practice, the smoke cloud is assumed to be the entire distance of the beam path; therefore, the total obscuration required for alarm should be selected by setting the Sensitivity Pot Setting as recommended in
Section 7.2 Sensitivity Adjustment on page 5.
The detectors automatically compensate for the effects of dust or dirt accumulation on the covers and for component aging. The NFPA requires that the detector's sensitivity be measured in the field, and requires that these measurements be made within one year after initial installation and every alternate year thereafter (reference NFPA
72). A TK240 Test Kit should be ordered to test the unit’s sensitivity in the field. The chart ( Figure 19) below represents alarm information for the filters in the TK240 as well as the Sensitivity Test Kit provided with the units.
Since the total obscuration of the beam by smoke increases with distance between the units (because more smoke will be within the beam path), the detector can be made less sensitive as the distance increases. Additionally, the sensitivity of the detector should be made less at greater distances because obscuration by other contaminants such as dust increases. The sensitivity should be set to respond to the proper smoke obscuration and also to reduce the chance of a false activation.
As shown in Figure 17, if the expected smoke density is 0.5 percent per ft (per 30 cm), the obscuration at 50 ft (15 m) is 20 percent and at
250 ft (95 m) it is 73 percent.
S e
S n
0
1
e s i t
2 o
t
4
5
7 r o r
i t i n v i
3
6
g t y M u s t N O T
A l a r m
0 %
0 %
( n o
( n o f i l t e r ) f i l t e r )
2 0 %
2 0 % f i l t e r f i l t e r
4 0 % f i l t e r
4 0 % f i l t e r
M
A l
U a
4 0 %
6 0 %
S r
Figure 19 - Sensitivity/Response Chart
T m
f i l t e r f i l t e r
6 0 % f i l t e r
8 0 % f i l t e r
8 0 % f i l t e r
8 0 % f i l t e r
DS240/DS241 Installation Instructions © 2004 Bosch P/N: 22066P Page 7
The Sensitivity Test Kit (supplied) may be used to check the sensitivity of the detectors during installation only. For field testing, the TK240 must be used. Each filter decreases the detector’s signal by a defined amount. When each filter is placed in front of the receiver’s optical module for at least 30 sec (5 sec for position 0 or 1), the approximate sensitivity setting of the installed detector can be determined by the detector's response as shown in Figure 19 on page 7.
NOTE: Testing these detectors will activate a fire alarm. Be sure to inform all concerned personnel before performing and testing.
8.8 FCC Compliance Notice
This equipment has been tested and found to comply with the limits for a class B digital device, pursuant to Part 15 of the FCC Rules.
These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates, uses, and can radiate radio frequency energy and, if not installed and used in strict accordance with the manufacturer's instructions and recommendations, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation. If this equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment on and off, the user is encouraged to try to correct the interference by one or more of the following measures:
• Re-orient or relocate the receiving antenna.
• Increase the separation between the equipment and the receiver.
• Connect the equipment into an outlet on a circuit different from the receiver.
• Consult the installing company or an experienced radio/TV technician for help.
The booklet, "How to Identify and Resolve Radio-TV Interference
Problems,” prepared by the Federal Communications Commission
(FCC) may prove helpful. This booklet is available from the U. S.
Government Printing Office, Washington, DC 20402. Please specify
Stock No.004-000-00345-4.
Page 8 P/N: 22066P © 2004 Bosch DS240/DS241 Installation Instructions
9.0
Troubleshooting
DS240/DS241 Installation Instructions © 2004 Bosch P/N: 22066P Page 9
10.0 Installing Multiple Units
Page 10 P/N: 22066P © 2004 Bosch DS240/DS241 Installation Instructions
11.0 Quick Start Installation Flow Chart
DS240/DS241 Installation Instructions © 2004 Bosch P/N: 22066P Page 11
© 2004 Bosch
130 Perinton Parkway, Fairport, NY 14450-9199 USA
Customer Service: (800) 289-0096; Technical Support (888) 886-6189
22066P
Installation Instructions
7/04
DS240/DS241 Long Range Beam Smoke Detectors
Page 12 of 12
