Vaisala GMW45 Technical data

P.O. Box 26, FIN-00421 Helsinki, FINLAND

Tel: [phone]

Fax: [phone]

Email: [e-mail]

www.vaisala.com

GMW45 Carbon Dioxide Transmitters
for Demand Controlled Ventilation Applications

Features/Benefits

• Compact wall mount transmitter

for demand controlled ventilation

• Incorporates Vaisala CARBOCAP®

Sensor - the silicon-based NDIR
sensor

• Excellent long-term stability

• Five year recommended calibration

interval

• Easy-to-install

Vaisala CARBOCAP® Carbon Dioxide Transmitter GMW45 is a basic wall mount transmitter for
demand controlled ventilation.

The wall mount Vaisala CARBOCAP®
Carbon Dioxide Transmitter GMW45 is
ideal for monitoring the air quality in
public, commercial and residential
buildings. By monitoring CO2 in air
with GMW45 and ventilating only on
demand, indoor air can be kept fresh
with no wasted energy.

Vaisala CARBOCAP

®

technology

The GMW45 transmitter features a
silicon-based Vaisala CARBOCAP®
Sensor. Due to its built-in reference
measurement capabilities and simple
structure, the sensor is extremely
stable and reliable.

The temperature dependence of
CARBOCAP® is negligible. In addition,
the measurement accuracy of the
sensor is not affected by dust, water
vapor or most chemicals.

Easy maintenance

The recommended calibration interval
for the GMW45 transmitter is five
years. The use of the GMW45 results in
considerable savings in energy
consumption, maintenance and
recalibration costs, and it ensures the
best possible control of air quality.

Basic DCV transmitter

The GMW45 is a basic cost-effective
CO2transmitter intended to be used in
building energy management systems.
It is easy to install. If CO2transmitters
with additional measurements are
required, Vaisala offers a wide variety of
wall and duct mount CO2, CO2+T, RH
and RH+T transmitters for demand
controlled ventilation.

94 Vaisala Instruments Catalog 2005

94

Ref. B210435en rev. A

GMW45

24V OUTGND

0-10V
0-20mA
4-20mA

0-10V

0-20mA

4-20mA

SELECTED

SELECTED

SELECTED

POWER
SUPPLY

ANALOGUE
OUTPUT

OUTPUT
SELECTION
JUMPERS

OUT24V GND

Technical Data

CARBON DIOXIDE

Carbon dioxide

Measuring range 0...2000 ppm CO
Accuracy at +25 °C (+77 °F) against
certified factory references

<±[40 ppm CO

(includes repeatability and

+ 3% of reading]

2

calibration uncertainty)
Non-linearity <±1.0 %FS
Temperature dependence 0.15 %FS /°C
of output (typically)
Long-term stability <5.0 %FS /5 years
Recommended calibration interval 5 years
Response time (0...63%) 1 minute

Operating conditions

Operating temperature range -5…+45 °C (23 …113 °F)
Humidity range 0...85 %RH

non-condensing

General

Output signals for CO

2

Resolution of analog outputs 10 ppm CO
Recommended external load:

current output max. 500 Ohm

voltage output min. 1 kohm
Power supply nominal 24 VAC/VDC
Power consumption <2.5 W
Warm-up time 1 minute

30 minutes full specification
Housing material ABS plastic
Weight 75 g
Complies with EMC standard EN61326-1:1997 + Am1:1998 +
Am2:2001; Generic Environment.

Selectable

0...20 mA or

4...20 mA or

0...10 V

Dimensions

2

Dimensions in mm

Wiring

2

CARBOCAP® is a registered trademark of Vaisala.
Specifications subject to change without prior notice.
©Vaisala Oyj

Accessories

GM35001 Calibration pipe
19222GM Calibration software kit

GM70 hand-held carbon dioxide meter
GM70 w/pump option hand-held CO2 meter for field verification

Ref. B210435en rev. A

(includes disk and serial COM adapter)

95Vaisala Instruments Catalog 2005

95