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CO detector Carbon Monoxide Alarm AC or DC power NC NO output

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Toxic gas detector and gas alarm of environment security sensor.

CO303 AC power wire in or plug in type or CO343A DC9-28VDC power relay NC or NO output with connection for home security system or fire alarm system.

CO303 or CO343A is for CO detection used in the home, small commercial properties, recreational vehicles.

Easy to install

Loud 80dB alarm and LED warning light

High quality durable sensor

Self diagnostic function by MCU intelligent software

EN54 certificated professional fire alarm component

Unit Dimensions: 120mm(H)*72mm(W)*42mm(D)

Color: Ceiling white

Operating Temperature: -10C to +50C

Alarm Horn: 80dB

Operation voltage: CO303: AC 90-270VAC

CO343A DC9-28VDC

Power consumption: <1.5W (standby), <5W (Alarm)

Alarm Response time

>100ppm (Alarm in less than 15 minutes)

>300ppm (Alarm in less than 3 minutes)

Alarm: Red LED with 80dB alarm

Warm up time: approximately 60 seconds

Alarm output: Relay output (2A @ DC 24V, 1A@220VAC) --for CO343A only


1. Power light (green)

2. Fault light (yellow)

3. Test /Mute/ Reset button

4. Gas Alarm light (Red)

5. Behind the cover, alarm horn 80dB audible alarm for test, alarm, and unit malfunction warning.

Installation shall only be undertaken by technicians holding a certificate issued by an authorized distributor.

If your bedroom hallway is longer than 40 feet, install a CO alarm at both ends of the hallway.

Install at least one CO alarm near or within each separate sleeping area.

For added protection, install an additional CO alarm at least 20 feet (6 meters) away from the furnance or fuel burning heat source.

Dangerous levels of Carbon monoxide:

50 ppm: The maximum allowable concentration for continuous exposure for healthy adults in any 8-hour period. according to OSHA.

200 ppm: Slight headache, fatigue, dizziness, nausea after 2-3 hours.

400 ppm: frontal headaches, within 1-2 hours, life threatening after 2-3 hours.

800 ppm: Dizziness, nausea and convulsions within 45 minutes. Unconsciousness within 2 hours. Dealth within 2-3 hours.
    • UPC 782123753833
    • Mfg Part # CO-303
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Other Policies

Household alarms should be as necessary as household appliances. But home alarms are special products.It plays an important role in keeping the family safe.Therefore, the installation and use of family alarm should be based on the home environment safety needs and alarm installation requirements. For wireless alarm, different manufacturers, different brands of alarm equipment is not compatible. Therefore, before buying an alarm, carefully read the product description and understand the brand of the product to determine its wireless compatibility.
There are many kinds of alarms. Alarm manufacturers designed a variety of alarms for different users of different habits or environmental differences. Therefore, you can choose the most appropriate alarm according to your own security needs.
Before buying alarm equipment, you should understand the functions and characteristics of all kinds of alarms and your own security needs. If you have any questions, please contact the product seller. Professional alarm equipment sales will provide detailed product installation instructions, video demonstrations, and technical guidance.
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