Carbon Monoxide Transmitter, Wall Mount (AI-CO)

Product overview

The AI-CO is a wall mounted carbon monoxide transmitter. An electrochemical sensor that meets UL2034, EN50291, and EN54-31 requirements measures CO in the surrounding air, and the transmitter sends the reading as an analog signal that your BMS, PLC, or ventilation controller can act on. It has no display of its own, so it sits quietly on the wall and works in the background.

For a building, that means people in garages, plant rooms, and service areas are covered by continuous monitoring, and exhaust fans can run when the air needs them instead of all day. An optional relay and an optional RS-485 Modbus link let it switch a fan or report to a central system, and an optional buzzer gives a local alert.

How it works

The electrochemical sensor reacts to carbon monoxide in the air, and the transmitter turns that reaction into a standard output, either 4 to 20 mA or 0 to 10 VDC, which you select in the field. The sensor reaches 90% of its final reading within 60 seconds (T90). Four tactile keys on the unit are used for settings. The optional relay can start a fan or other equipment when the CO level crosses the point you program, the optional buzzer sounds a local alert, and the optional RS-485 Modbus link carries the reading to a monitoring system.

Protecting occupants and trimming fan energy

Carbon monoxide cannot be sensed by people, so the only dependable way to know it is rising is an instrument. A transmitter on the wall gives your building continuous awareness of the air in spaces that are easy to forget until something goes wrong.

It also helps the building run efficiently. In a garage, for example, exhaust fans that respond to a CO signal run only when they are needed, instead of all day, so energy is spent where it protects people.

Features

• Electrochemical CO sensing

  A UL recognized sensor that meets UL2034, EN50291, and EN54-31 requirements.

• Three ranges

  0 to 100 ppm, 0 to 250 ppm, or 0 to 500 ppm, chosen when you order.

• Field selectable output

  4 to 20 mA or 0 to 10 VDC, set on site.

• Optional relay

  One programmable relay with NO, CO, and NC contacts, rated 2 A.

• Optional buzzer alarm

  A programmable built in buzzer for a local audible alert.

• Optional RS-485 Modbus

  A digital connection to BMS, PLC, and monitoring systems.

• Stable over time

  Less than 5% signal loss per year.

• Quick response

  T90 within 60 seconds.

• Wide reach

  A typical coverage area of 700 m² (7500 ft²), or a 15 m (50 ft) radius.

• Compact wall enclosure

  ABS plastic, 104 x 85 x 48 mm.

• Simple wiring

  Screw terminals for 24 VDC power and the output signal.

Applications

• Parking lots and garages

  Watches the air where vehicle exhaust builds up, and gives the exhaust fans a signal so they run when CO rises rather than continuously, which saves fan energy.

• Boiler rooms

  Keeps watch over spaces where combustion equipment can release CO, protecting the staff who work there and the occupants above.

• Mines

  Provides CO monitoring in underground working areas where air quality has to be tracked.

• Boats and marine applications

  Monitors enclosed spaces on vessels where engines and heaters can raise CO.

• Oil and gas facilities

  Covers plant areas where combustion processes generate CO.

• Semiconductor manufacturing environments

  Supports CO monitoring in process areas that need controlled air.

Choosing your configuration

Choosing the measuring range

All three versions measure the same gas, and the only difference is the top of the range.

• 0 to 100 ppm

  For spaces where you expect low concentrations and want finer readings across a small span.

• 0 to 250 ppm

  A middle range with more headroom.

• 0 to 500 ppm

  For areas where higher concentrations are possible.

Choose the range that matches the levels you expect, and note that it is set when you order.

Choosing the output

• 4 to 20 mA

  Suits most BMS, PLC, and controller analog inputs, and is the usual choice for longer cable runs.

• 0 to 10 VDC

  Suits controllers that expect a voltage signal.

The output is selected in the field, so the same transmitter can be set up for either type when you install it.

Ways the transmitter can respond

• Optional relay

  Switches a fan starter or other equipment, so the transmitter can start ventilation on its own. Design the external load and control circuit within the 2 A rating.

• Optional buzzer

  Gives people near the transmitter an audible alert without depending on a screen elsewhere.

• Optional RS-485 Modbus

  Reports to a BMS, PLC, or central monitoring system.

Installation and maintenance

Where to mount it

The AI-CO is a wall mounted transmitter, and it is not installed in a duct. Mount it on the wall near the point where the airflow starts in the space you are monitoring. Think about where CO is likely to come from, the layout of the room, and the ventilation arrangement.

When mounted on a wall, the sensing area is reduced to approximately half the size. The sensing radius is negatively impacted when interfering factors impact the coverage area. It is subject to proper placement, adequate ventilation and other environmental factors.

It is paramount to place sensors in a manner that ensures maximum coverage area. Some location factors to keep in mind that may negatively impact the sensing radius while planning include:

• Exhaust Vents: Avoid placing sensors directly under exhaust vents. The airflow can disrupt CO reaching the sensor, potentially delaying detection.
• Dead Zones: Stagnant air pockets can trap CO, preventing it from reaching the sensor. Avoid corners, behind pillars, or other areas with minimal air circulation.
• Non-overlapping, Comprehensive Coverage: Each floor of the parking structure requires complete sensor coverage without any redundant areas.
• Wall v/s Pillar Mounting: Wall mounting reduces the detection radius, opt for pillar mounting wherever possible, to ensure maximum utilization of detection radius.

Maintenance

Gas sensors need periodic checks. Inspect the transmitter and confirm its performance on a schedule that follows your site's gas detection maintenance procedures. Ask our team about calibration and sensor replacement requirements for your application.

Specifications

Need wiring details or a dimensional drawing? Ask our engineers or write to sales@iaqdetectors.com.

How to order

The model code is built as AI-CO, then Range, then Relay, then Communication. For example, AI-CO-250-100-MOD is a 0 to 250 ppm transmitter with one relay and RS-485 Modbus.

Compliance

• SensorThe sensor inside the AI-CO is a UL recognized electrochemical sensor meeting UL2034, EN50291, and EN54-31 requirements.
• Complete transmitterThat describes the sensor, and it is not a certification of the complete transmitter unless separately documented.
• Your safety arrangementsThe transmitter provides the measurement, alarm outputs, and signals for BMS integration, and it assists your safety arrangements. You set the alarm points from your own risk assessment and local requirements.
• Quality systemAce Instruments manufactures under an ISO 9001:2015 certified quality management system.

Frequently asked questions