Carbon dioxide measurement

Measurement range


Accuracy (including repeatability, non-linearity and calibration uncertainty)
Sensor

0 ... 2000 ppm (nominal; can be calibrated for other ranges:
0 ... 5000 ppm, 0 ... 10 000 ppm, 0 ... 20 000 ppm)


±(2 % of range + 2.0 % of reading)
Vaisala CARBOCAP^®

Temperature measurement (optional with GMW21)

Measurement range
Accuracy at +25 °C
Sensor

0 ... +50 °C (+32 ... +122 °F)
± 0.5 °C (± 0.9 °F)
Semiconductor IC

Operating environment

Temperature
Humidity

-5 ... +45 °C (+23 ... 113 °F)
0 ... 85 %RH non-condensing

Inputs and outputs

Outputs
Optional outputs
Operating voltage
Power consumption

0 ... 20 mA or 4 ... 20 mA and 0 ... 10 V
relay, LonWorks^® interface
nominal 24 VAC/DC (18 ... 30 VDC)
<2.5 W

Mechanics

Weight
     GMD20(D)
     GMW21 (D)
     GMW22 (D)
Housing material
Housing classification (electronics housing GMD20)

140 g (170 g)
100 g (130 g)
 90 g (120 g)
ABS plastic

IP65 (NEMA 4)

Options and accessories

GMI21
GMR20
GML20

GML20T

19222GM
GMA20T

GM70 w/pump option

Display and relay option for GMD/W21/22
Relay output option
LonWorks^® module with CO₂ signal (not available when the display option is added)
LonWorks^® module with both CO₂ and temperature signals (not available when the display option is added)
Calibration software kit (disk serial COM adapter)
Analog temperature module for GMW21 (not available when the display option is added)
Hand-held CO₂ meter for field verification