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D200-09-00
1
I56-0058-004R
7251 intelligent Laser Smoke Sensor
inStaLLatiOn and maintenanCe inStrUCtiOnS
3825 Ohio Avenue, St. Charles, Illinois 60174
1-800-SENSOR2, FAX: 630-377-6495
www.systemsensor.com
BeFOre inStaLLing
This sensor must be installed in compliance with the control panel system
installation manual. The installation must meet the requirements of the Au-
thority Having Jurisdiction (AHJ). Sensors offer maximum performance when
installed in compliance with the National Fire Protection Association (NFPA);
see NFPA 72.
generaL deSCriPtiOn
Model 7251 is a plug-in type smoke sensor that uses a laser based sensing
chamber. The sensor uses analog-addressable communications to transmit
smoke density and other information to the control panel. Rotary-decade
switches are provided for setting the sensor’s address. Two LEDs on the sensor
are controlled by the panel to indicate sensor status. An output is provided for
connection to an optional remote LED annunciator (P/N RA400Z).
This detector requires compatible addressable communications to function
properly. Connect this sensor to listed-compatible control panels only.
SPaCing
System Sensor recommends spacing sensors in compliance with NFPA 72. In
low air flow applications with smooth ceilings, space sensors 30 feet apart. For
specific information regarding sensor spacing, placement, and special applica-
tions, refer to NFPA 72 or the System Sensor
Guide For Proper Use of System
Smoke Detectors
, available from System Sensor (P/N I56-407-XX).
Wiring inStrUCtiOnS
All wiring must be installed in compliance with the National Electrical Code,
applicable local codes, and any special requirements of the Authority Having
Jurisdiction. Proper wire gauges should be used. The installation wires should
be color-coded to limit wiring mistakes and ease system troubleshooting. Im-
proper connections will prevent a system from responding properly in the
event of a fire.
Remove power from the communication line before installing sensors.
All wiring must conform to applicable local codes, ordinances, and regula-
tions.
1. Wire the sensor base (supplied separately) per the wiring diagram, see
Figure 1.
2. Set the desired address on the sensor address switches, see Figure 2.
3. Install the sensor into the sensor base. Push the sensor into the base while
turning it clockwise to secure it in place.
4. After all sensors have been installed, apply power to the control unit and
activate the communication line.
5. Test the sensor(s) as described in the TESTING section of this manual.
SPeCiFiCatiOnS
Operating Voltage Range:
15 to 32 VDC
Standby Current:
330µA @ 24 VDC (one communication every 5 sec. with LED blink enabled)
Max. Alarm Current (LED on:)
6.5 mA @ 24 VDC
Operating Humidity Range:
10% to 93% Relative Humidity, noncondensing
Operating Temperature Range:
0°C to 38°C (32°F to 100°F); U.S.
–10°C to 50°C (14°F to 122°F); Europe (this range not evaluated by UL)
Height:
1.7 inches (43 mm) installed in B210LP Base
Diameter:
6.1 inches (155 mm) installed in B210LP Base
4.1 inches (104 mm) installed in B501 Base
Weight:
5.0 oz. (142 g)
Additional Bases Available:
All 200/500 Series bases are compatible.
I56-0058-004R
teSting
Before testing, notify the proper authorities that the system is undergoing
maintenance, and will temporarily be out of service. Disable the system to
prevent unwanted alarms.
All sensors must be tested after installation and periodically thereafter. Test-
ing methods must satisfy the Authority Having Jurisdiction (AHJ). Sensors
offer maximum performance when tested and maintained in compliance with
NFPA 72.
The sensor can be tested in the following ways:
A. Functional: Magnet Test (P/N M02-04-01 or M02-09-00)
This sensor can be functionally tested with a test magnet. The
test magnet electronically simulates smoke in the sensing cham-
ber, testing the sensor electronics and connections to the control
panel.
1. Hold the test magnet in the magnet test area as shown in Figure 3.
2. The sensor should alarm the panel.
Two LEDs on the sensor are controlled by the panel to indicate sen-
sor status. Coded signals, transmitted from the panel, can cause the
LEDs to blink, latch on, or latch off. Refer to the control panel tech-
nical documentation for sensor LED status operation and expected
delay to alarm.
B. Smoke Entry: Aerosol Generator (Gemini 501)
The GEMINI model 501 aerosol generator can be used for smoke
entry testing. Set the generator to represent 4%/ft. to 5%/ft. ob-
struction as described in the GEMINI 501 manual. Using the bowl
shaped applicator, apply aerosol until the panel alarms.
A sensor that fails any of these tests should be cleaned as described under
CLEANING, and retested. If the sensor fials after cleaning, it must be replaced
and returned for repair.
When testing is complete, restore the system to normal operation and notify
the proper authorities that the system is back in operation.
CAUTION
Dust covers provide limited protection against airborne dust particles during
shipping. Dust covers must be removed before the sensors can sense smoke.
Remove sensors prior to heavy remodeling or construction.