PMsense – Particulate Matter Transmitter

Outdoor air quality monitoring

This PM1.0, PM2.5 and PM10 particulate matter transmitter delivers its readings over an RS485 Modbus-RTU output. Dust particle concentration is measured by laser scattering; response is fast, sensitivity high and stability excellent, and no maintenance is required.

Two ways to run the PM sensor

• Continuous: the sensor stays active and measures all the time; this mode guarantees at least 10,000 hours of PM sensor life.
• Discontinuous (default): the sensor switches on at regular intervals, only when a measurement is due, which extends its life.

Options

• CO2 sensor integrated in the transmitter, on request
• Up to 2 configurable analog outputs: 4…20 mA, 0…5 V or 0…10 V

General specifications

• Output: RS485 with Modbus-RTU or proprietary ASCII protocol
• Power supply: 7…30 VDC
• Consumption: discontinuous (default), 25 mA @ 24Vdc while measuring and 4 mA in standby; continuous, 25 mA @ 24Vdc
• Connection: 8-pole M12 circular connector
• Operating conditions: -20…+70 °C; 500…1500 hPa
• Housing: polycarbonate
• Protection class: IP53; sensor air inlet filter housing resistant to rain and UV rays
• Dimensions: 120 x 94 x 71 (M12 connector excluded)
• Weight: 330 g

Particulate measurement

• Principle: laser scattering
• Pollutants measured: PM1.0, PM2.5 and PM10
• Measuring range: 0…1000 μg/m3 for each pollutant
• Particle size detection range: ø 0.3…10 μm
• Linearity error: < 5%
• Repeatability: < 3%
• Warm-up time: 15 s
• Sensor operating mode: discontinuous (default), 5-minute interval ≈ 5 years of life; continuous, 1-second interval ≈10,000 h of life
• Temperature drift: < 0.01 μg/m3 /°C

CO2 (optional)

• Principle: dual-wavelength NDIR
• Measuring range: 0…5000 ppm
• Accuracy: ±(50 ppm+3% of reading) at 25 °C and 1013 hPa
• Response time: < 120 s (air speed = 2 m/s)
• Long-term stability: 5% of reading / 5 years
• Temperature drift: 1 ppm/°C