Indoor air quality

with Modbus communication

Siro-MOD

Multifunctional indoor air quality transmitters for building automation systems that use Modbus serial communication protocol

Siro-MOD is an indoor air quality transmitter with a modern design. The transmitter is available with several optional air quality sensors. The modular device can be equipped with CO2 concentration and VOC (Volatile Organic Compounds) measurements or alternatively PM (Particulate Matter) measurement, and in addition, temperature and humidity measurements. It offers easy installation and adjustment, several different model options and various output signals that are configurable separately for each measurement parameter.

 

The Siro-MOD series devices are available with a user interface that includes an LCD display and buttons making the configuration of the device quick and easy. An external configuration tool is necessary for commissioning preparations for Siro-MOD without the user interface. Configuration is also possible via Modbus network. Siro-MOD utilizes the industry standard NDIR measurement principle with self-calibrating ABC logicTM for CO2 measurement.

 

Siro-MOD series devices include:

  • Several options for indoor air quality measurements (CO2, VOC, PM, rH, T).
  • Field configurable outputs for selected measurements.
  • Proportional output options including voltage (0–10 V, 0–5 V, 2–10 V) and optional current (4–20 mA).
  • Offset feature enabling field calibration for each measurement parameter (CO2, VOC, PM, rH, T).
  • Optional LCD-display and buttons.

Technical details

Communication: RS-485 Modbus (RTU)
Accuracy:
 CO₂: ±40 ppm + 3 % of reading (typical),
additional ±60 ppm for first weeks
Relative humidity: ±2.2 % rH (typical at 20 °C, 30 % rH)
Temperature: ±0.4 °C (typical at 20 °C)
VOC: ±15 % of reading (typical)
*VOC sensor is tuned for typical IAQ Mix of 22 VOCs as defined by Mølhave et al. (1997)
PM:
0…100 μg/m3:
PM2.5: ±15 μg/m3(at 25 ⁰C ±5 ⁰C)
PM1/PM10*: ±25 μg/m3 (at 25 ⁰C ±5 ⁰C)
100…1000 μg/m3:
PM2.5: ±15 % (at 25 ⁰C ±5 ⁰C)
PM1/PM10*: ±25 % (at 25 ⁰C ±5 ⁰C)
*PM1 and PM10 values are calculated from PM2.5 measurement reading with the default particle distribution.
Measuring elements: CO2: Non-dispersive infrared (NDIR)
VOC: Complementary Metal Oxide Semiconductor (CMOS)
PM: Laser-based light scattering particle sensing
Temperature: Integrated to CMOS
Relative humidity: Thermoset polymer capacitive sensing element
Measuring units: CO2: ppm
Relative humidity: % rH
Temperature: °C
VOC CO2eq: ppm
TVOC: ppm, μg/m3
PM1/2.5/10: μg/m3
Calibration (CO2): Automatic self-calibration, ABC LogicTM
Supply voltage: 24 VDC/VAC ±10 %
Output signal 1–4: 0...10 V (optional 2...10 V / 0...5 V, display or configuration tool required)
Optional 4...20 mA
Linear to selected measurement (CO2, VOC, PM, rH or Temp)
Operating temperature: 0...50 °C
Protection standard: IP20
Product datasheet Installation instructions User guide EU Declaration of Conformity UK Declaration of Conformity

Siro-MOD

Example
Siro-CO2-T-D

Model

Product series

Siro
Indoor air quality transmitter
Siro

Model type

-MOD
With Modbus communication
-MOD

CO2 sensor

-CO2
With CO2 sensor (option not available with PM sensor)
Without CO2 sensor

VOC sensor

-VOC
With VOC sensor (option not available with PM sensor)
Without VOC sensor

PM sensor

-PM
With PM sensor (option not available with CO2 and VOC sensors)
Without PM sensor
-PM

Relative humidity sensor

-rH
With relative humidity sensor
Without relative humidity sensor (option not available with VOC sensor)

Temperature sensor

-T
With temperature sensor
Without temperature sensor (option not available with VOC or rH sensor)
-T

Output

Voltage output
-A
Voltage and current output

Display

-D
With display
Without display
-D

Other Indoor air quality: