Asense-Room

Supported Applications

The ACI ASENSE Room series monitors carbon dioxide (CO2) levels in commercial, school, and office environments. Based on single beam non-dispersive infrared technology, the sensor measures CO2 concentration up to 2,000 ppm and provides an analog temperature output. Documented applications include commercial office buildings, gyms, shopping malls, auditoriums, theaters, hospitals, and schools.

Operating Conditions & Performance

The series operates in residential, commercial, and industrial spaces with a specified operating environment of 32°F to 122°F (0°C to 50°C) and relative humidity from 0 to 85% RH Non-condensing. The sensing range covers CO2: 0 to 2000 ppm and Temperature: -4 to 140°F (-20 to 60°C). Accuracy is defined as ±30 ppm and ±3% of reading for CO2, and ±1.8°F (1°C) for temperature; this accuracy applies after a minimum three ABC periods where one period equals 8 days.

Performance characteristics include repeatability of ±20 ppm ±1% of measured value and an annual zero drift of <± 0.3% of measurement range. The response time is listed as <10 seconds @ 30 cc/minutes flow rate, with a diffusion time of <3 minutes. Warm-up time requires less than 5 minutes to reach full specifications (or 15 minutes). Operating pressure compensation is +1.6% per 0.145 psi (1 kPa) deviation from normal pressure (1 Atmosphere = 14.7 psi (1.013 KPa)). The sensor life exceeds 15 years.

Configuration Options

The ASENSE Room series supports configurable output signals and optional relay functionality via hardware jumpers or programming cable configuration. Power supply requirements are 24 VAC/VDC ±20%; 50/60 Hz, with a maximum of 10.5 to 40 VDC (Half-wave rectified). The enclosure is constructed from ABS material with a Flammability Rating UL94-HB.

Available output configurations include:

• Output 1 (CO2): 0/2 to 10V, 0/4 to 20 mA, or 0 to 2000 ppm.
• Output 2 (Temperature): 0/2 to 10V, 0/4 to 20 mA, covering 32 to 122°F (0 to 50°C).
• Output 3: N.O. or N.C. relay rated at 0.5A @ 125 VAC; 1A @ 24 VDC.

The series supports extended CO2 ranges up to 10,000 ppm when factory set or configured via programming cable. Extended range accuracy for readings > 2,000 PPM is ±30 ppm and +/5% of reading. Configuration options include the Sensear ABC algorithm (Automatic Baseline Correction), which requires building CO2 levels to drop to 400 ppm some time during the week; if occupied 24 hrs/day, ABC must be turned off.

Accessories for configuration and calibration include:

• TTL-232R-3V3 Programming Cable
• UIP5 Free Software Download (Contact ACI)
• A/CUSTOM CAL GAS* Custom Calibration

Key Product Differences

The series is offered in standard and display-equipped models, with or without relay output. The ASENSE-R-LCD variant includes a 4 digits, 7 segments LCD with ppm indicator for self-diagnostics via yellow LED and error indication.

• ASENSE-R: CO2 Room sensor with analog outputs (0-10 VDC or 0-20 mA), field selectable to 4-20mA or 2-10 VDC. Weight: 0.300 lbs (0.136 kg).
• ASENSE-R-LCD: Includes display with analog outputs and weight of 0.314 lbs (0.142 kg). Storage temperature for LCD versions is -4 to 122°F (-20 to 50°C), whereas standard versions store from -40 to 158°F (-40 to 70°C).
• ASENSE-R-REL: Includes relay output (N.O. or N.C.) with factory set trip point at 1000 ppm and deadband/hysteresis of 100 ppm.
• ASENSE-R-LCD-REL: Combines display functionality with the optional relay configuration.