Elvaco offers temperature and humidity sensors, both for indoor and outdoor environments. The product line enables simple and cost-effective metering, which enables a more effective use of energy and a better real-estate climate. Sensors are available with M-Bus or Wireless M-Bus communication, as well as with or without display.  


CMa12w - Indoor temperature sensor, Wireless M-Bus

The CMa12w is a one-way wireless M-Bus temperature sensor for indoor use. The sensor offers high accuracy and user-friendliness as well as a long battery-life (up to 15 years) which makes it the optimal choice for tenant owners. Readout and configuration are easily performed via wireless M-Bus or by using a mobile phone (via NFC).


Casing material:
ABS UL94-V0, white
Protection class:
Dimensions (w x h x d):
80 x 80 x 25 mm
75 g

Electrical connections

Supply voltage:
Battery, life span 15 years (at 15 °C to 25 °C)

Electrical characteristics

Environmental specifications

Operating temperature:
-10 °C to +50 °C
Operating humidity:
0 to 95 %, no condensation
Operating altitude:
0-2000 m
Pollution degree:
Degree 2
Usage environment:
Storage temperature:
-40 °C to +85 °C
Measurement range, temperature sensor:
-20 °C to +55 °C

Temperature sensor, margin of error

Temperature: 5 °C to 55 °C:

Humidity sensor, margin of error

User interface

Momentary values:
Temperature, status
Historic values:
Average value over the last hour and last day


Wireless M-Bus

Integrated M-Bus Master

Wireless M-Bus Receiver

M-Bus slave interface

Frequency, Wireless M-Bus:
868.95 MHz
Transmit power:
10 mW
Transmit interval:
3 minutes
Wireless M-Bus modes:
C1 (default) and T1


Data storage (examples)

Mobile Network

Fixed Network (Ethernet)



EN 61000-6-2, EN 61000-6-3

Connections and Interfaces


For downloads, please visit our support site at:

Our website has gathered all resources you need to update, tune and troubleshoot your installations, such as:

  • Latest software versions
  • FAQs
  • Guides
  • In-depth technical information
  • Support forum

We use cookies to give you a better user experience. If you want to know more about cookies and how we use them, please visit our cookie page. Continued navigation on the site means you accept our cookie policy. Learn more