System Sensor 2424 User manual

D400-06-00 1 I56-286-05R
2412B, 2412THB, 2424, and 2424TH
Direct Wire Photoelectronic
Smoke Detectors
INSTALLATION AND MAINTENANCE INSTRUCTIONS
3825 Ohio Avenue, St. Charles, Illinois 60174
1-800-SENSOR2, FAX: [phone]
ww.systemsensor.com
Before Installing
Please thoroughly read the System Sensor manual A05-
1003, Applications Guide for System Smoke Detectors,
which provides detailed information on detector spacing,
placement, zoning, wiring, and special applications. Copies
of this manual are available at no charge from System
Sensor. (For installation in Canada, refer to CAN/ULC-
S524, Standard for the Installation of Fire Alarm Systems
and CEC Part 1, Sec. 32.)
General Description
System Sensor 2412 and 2424 photoelectronic smoke detec-
tors utilize state-of-the-art, optical sensing chambers. These
detectors are designed to provide open area protection, and
to be used with compatible UL-listed 4-wire control panels
only. The 2412 applies to 12 volt panels and operates at
12VDC, and the 2424 applies to 24 volt panels and operates
at 24VDC. Operation and sensitivity can be tested in place.
Models 2412TH and 2424TH have the same specifications
as models 2412 and 2424, but in addition feature a built-in
fixed temperature (135°F) thermal detection unit.
Specifications
Diameter: 5.5 inches (14 cm)
Height: 3.19 inches (81 mm); Add 0.5 inches (1.3 cm) for thermal units
Weight: 0.7 lb (310 g)
Operating Temperature Range: 2412 and 2424 — 0°C to +49°C (32°F to 120°F)
2412TH and 2424TH — 0° to +38°C (32° to 100°F)
Operating Humidity Range: 10% to 93% Relative Humidity
Maximum Air Velocity: 3000 Ft./Min. (15 M/S)
Latching Alarm: Reset by momentary power interruption.
Electrical Ratings 2412 2424
System Voltage: 12 24 DC (4V Maximum Ripple)
Supply Voltage: 11.3 20 VDC Minimum
17 29 VDC Maximum
Reset Voltage: .73 .8 VDC Minimum
Standby Current: 120 120 µA Maximum
Alarm Currents: 35 21.3 mA Minimum
77 40.6 mA Maximum
The alarm and auxiliary relay operate within the specified voltage ratings.
Start-up Time: 34 34 S Maximum
EOL Relay: A77-716 A77-716
Reset Time: 0.3 0.3
Relay Contacts – resistive or inductive (60% power factor) load:
Form A: 2.0A @ 30VAC/DC
Form C:* 0.6A @ 110VDC; 2.0A @ 30VDC
1.0A @ 125VAC; 2.0A @ 30VAC
(*For Canadian installations, relay contact rating is 2.0A @ 30VAC/DC)
An LED on each detector lights to provide a local alarm indi-
cation. It flashes every ten seconds indicating that power
is applied to the detector. The LED lights continuously in
alarm. These detectors also have the latching alarm feature
that resets only by a momentary power interruption.
Each detector contains one set of Form A contacts for con-
nection to the alarm-initiating circuit, and one set of Form C
auxiliary contacts. Supervision of detector power is accom-
plished by installing a Power Supervisory End-of-Line Relay
Module (A77-716 Series) at the end of the detector power
loop. When power is applied to and through the detectors,
the EOL Power Supervisory Module is energized. Its relay
contacts close and provide a closed series circuit in the con-
trol panel’s alarm-initiating loop. A power failure or a break
in the detector power loop de-energizes the EOL Module.
The relay contacts open and trigger a trouble signal at the
control panel.

D400-06-00 2 I56-286-05R
Mounting
Each 2412 and 2424 detector is supplied with a mounting
bracket kit that permits the detector to be mounted:
1. Directly to a 31 ⁄2 inch or 4 inch octagonal, 1
1
⁄2 inch deep
electrical box, (see Figure 1) or
2. To a 4 inch square electrical box by using a plaster ring
with the supplied mounting bracket kit.
Installation Wiring Guidelines
NOTE: Refer to releasing device manufacturer’s installa-
tion instruction for proper connections.
All wiring must be installed in compliance with the
National Electrical Code and all applicable local codes and
any special requirements of the authority having jurisdic-
tion, using the proper wire size. The conductors used to
connect smoke detectors to control panels and accessory
devices should be color-coded to reduce the likelihood of
wiring errors. Improper connections can prevent a system
from responding properly in the event of a fire.
For signal wiring (the wiring between interconnected
detectors), it is recommended that the wire be no smaller
than AWG 18. However, the screws and clamping plate, in
the base, can accommodate wire sizes up to AWG 12. The
use of twisted pair wiring for the power (+ and –) loop is
recommended to minimize the effects of electrical interfer-
ence.
Smoke detectors and alarm system control panels have
specifications for allowable loop resistance. Consult the
control panel manufacturer’s specifications for the total
loop resistance allowed for the particular model control
panel being used before wiring the detector loops.
NOTE: For system supervision – for terminals 1, 2, 7, and
8, do not use looped wire under terminals. Break
wire run to provide system supervision of connec-
tions.
NOTE: Contacts are shown in stand-by mode and will
transfer in alarm condition.
Wire connections are made by stripping about 3⁄8 inch of
insulation from the end of the wire, sliding the bare end
of the wire under the clamping plate, and tightening the
clamping plate screw.
Tamper-resistance Feature
This detector includes a tamper-resistant feature that pre-
vents removal of the detector without the use of a tool. To
make the detector tamper-resistant, break off the smaller
tab at the scribed line on the Tamper Resistant Tab, on the
detector mounting bracket (see Figure 2), then install the
detector. To remove the detector from the bracket once it
has been made tamper-resistant, use a small screwdriver to
depress the tamper-resistant tab located in the slot on the
mounting bracket and turn the detector counterclockwise
for removal.
TAMPER
RESISTANT
TAB
TO MAKE DETECTOR TAMPER RESISTANT,
BREAK OFF TAB EXTENSION
AT SCRIBED LINE
Figure 1. Flush mounting of 2412/2424 smoke
detector on 31⁄2 inch and 4-inch octagonal box:
Figure 2. 2412/2424 smoke detector mounting
bracket:
COMMON
N/O
N/C
AUXILIARY
CONTACTS
FORM C
456
78
21
+-
POWER
ALARM
CONTACTS
FORM A
N/O
S0164-00
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Figure 3. Wiring diagram for 2412/2424 series smoke detector used with 4-wire control panel:
S0165-00
S0168-00 S0140-00

D400-06-00 3 I56-286-05R
Installation
WARNING
Remove power from initiating-device circuits before install-
ing detectors.
1. Wire detector per installation guidelines.
2. Line up arrows on the detector with arrows on the
mounting bracket.
3. Turn the detector clockwise until the detector clicks into
place.
4. After all detectors have been installed, apply power to
the control unit.
5. Test the detector as described under TESTING.
6. Reset the detector at the System Control Panel.
7. Notify the proper authorities the system is in operation.
CAUTION
Dust covers provide limited protection against airborne dust
particles during shipping. Dust covers MUST be removed
before the smoke detectors can sense smoke. Remove sen-
sors before beginning heavy remodeling or construction.
CAUTION
Smoke detectors are not to be used with detector guards
unless the combination has been evaluated and found
suitable for that purpose.
Testing
Before testing, notify the proper authorities that the smoke
detector system is undergoing maintenance, and therefore
the system will temporarily be out of service. Disable
the zone or system undergoing maintenance to prevent
unwanted alarms.
Before testing the detector, look for the presence of the
flashing LED. If it does not flash, power has been lost to
the detector (check the wiring), or it is defective (return
for repair).
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Figure 4. Top and side views showing position of recessed test switch:
S0167-00
Detectors must be tested after installation and following
periodic maintenance. The 2412 and 2424 may be tested
as follows:
A. Recessed Test Switch
1. A test switch is located on the detector housing (see
Figure 4).
2. Push and hold the recessed test switch with a 0.1 inch
maximum diameter tool.
3. The detector’s LED should light within 5 seconds.
B. Calibrated Test Card (Model R59-18-00)
1. Remove the detector cover by placing a small-bladed
screwdriver in the side slot of the detector cover,
twisting slightly until the cover can be turned coun-
terclockwise for removal.
2. Insert the NO ALARM end of the test card fully into
the test slot (see Figure 5), then slide it counterclock-
wise until it stops.
3. The detector should not alarm after 20 seconds.
4. Remove the test card by sliding it clockwise before
removing, then insert the ALARM end.
5. The LED should latch on within 20 seconds, indicat-
ing alarm and annunciating the panel.
6. Put the cover back by gently rotating it clockwise
until it locks in place.
C. Test Module (System Sensor Model No. MOD400R)
The MOD400R is used with an analog or digital voltme-
ter to check the detector sensitivity as described in the
MOD400R manual.
D. Aerosol Generator (Gemini 501)
Set the generator to represent 4%/Ft. to 5%/Ft. obscu-
ration as described in the Gemini 501 manual. Using
the bowl shaped applicator, apply aerosol until unit
alarms. Detectors that fail these tests should be cleaned
as described under MAINTENANCE and retested. If the
detectors still fail these tests, they should be returned for
repair.

D400-06-00 4 I56-286-05R
©2004 System Sensor
System Sensor warrants its enclosed smoke detector to be free from
defects in materials and workmanship under normal use and service for a
period of three years from date of manufacture. System Sensor makes no
other express warranty for this smoke detector. No agent, representative,
dealer, or employee of the Company has the authority to increase or alter
the obligations or limitations of this Warranty. The Company’s obliga-
tion of this Warranty shall be limited to the repair or replacement of any
part of the smoke detector which is found to be defective in materials or
workmanship under normal use and service during the three year period
commencing with the date of manufacture. After phoning System Sensor’s
toll free number 800-SENSOR2 (736-7672) for a Return Authorization
number, send defective units postage prepaid to: System Sensor, Repair
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
S0169-00
E. Direct Heat Test (Models 2412TH & 2424TH only)
To test the bi-metallic thermal collector on the Models
2412TH and 2424TH, use a low powered heat gun or
blow dryer, aiming the heat source across the detector.
Hold the heat source about 12 inches (30 cm) from the
detector to avoid damaging the plastic. When the heat
rises to greater than 135°F, the detector will latch in
alarm. After the test, the bi-metallic collector will self-
restore.
Notify the proper authorities that the system is back on
line when tests are complete.
Maintenance
NOTE: Before removing the detector cover, notify the
proper authorities that the smoke detector system
is undergoing maintenance, and therefore the sys-
tem will be temporarily out of service. Disable the
zone or system undergoing maintenance to prevent
unwanted alarms.
1. Remove the detector cover by placing a small-bladed
screwdriver in the side slot of the detector cover, twist-
ing it slightly until the cover can be turned counterclock-
wise for removal.
2. Vacuum the screen carefully without removing it. If
further cleaning is required, continue with step 3, other-
wise skip to step 6.
3. Remove the screen by pulling it straight out (see Figure
5). Vacuum the inside.
4. Clean the vaned chamber piece by vacuuming or blow-
ing out dust and particles.
5. To replace the screen, orient it so that the arrow on
top aligns with the test module socket of the detector.
Carefully push the screen onto the base, making sure it
fits tightly to the chamber.
6. Replace the cover by gently rotating it clockwise until it
locks in place.
7. Notify the proper authorities the system is back on
line.
Figure 5. Removal of cover and screen for cleaning:
Please refer to insert for the Limitations of Fire Alarm Systems
Three-Year Limited Warranty
Department, RA #__________, 3825 Ohio Avenue, St. Charles, IL 60174.
Please include a note describing the malfunction and suspected cause
of failure. The Company shall not be obligated to repair or replace units
which are found to be defective because of damage, unreasonable use,
modifications, or alterations occurring after the date of manufacture. In
no case shall the Company be liable for any consequential or incidental
damages for breach of this or any other Warranty, expressed or implied
whatsoever, even if the loss or damage is caused by the Company’s neg-
ligence or fault. Some states do not allow the exclusion or limitation of
incidental or consequential damages, so the above limitation or exclusion
may not apply to you. This Warranty gives you specific legal rights, and
you may also have other rights which vary from state to state.