CTRT2A
CTRT2A
CTRT2A
CO
2
and temperature transmitters
A range of room transmitters for measuring carbon
dioxide concentration in indoor environments. The
transmitter has a built-in CO
2
sensor with working range
0...2000 ppm and output signal 0...10 V, as well as built-
in 0...10 V and PT1000 temperature sensors (working
range 0...50°C).
Transmitters with automatic calibration combining
measurement of CO
2
level and temperature in the same
casing. The sensors are mounted in the cover-part of
the casing. The cover is easy to detach from the back by
means of snap-in grips and detachable terminals. This
makes mounting easier. Furthermore, no cables have to be
disconnected, simplifying service and replacement.
The transmitters are intended for wall mounting in
HVAC systems.
CO
2
sensor
The CO
2
concentration is measured using infrared light,
a technique that measures the absorption in gases. It has
a reference measuring system that compensates values in
relation to changes in light intensity. This technique has
many advantages:
• Very high accuracy
• Exact identification of the detected gas
• Low risk of contamination
• Short response time
• Excellent long-term stability
Automatic calibration
The transmitters have automatic calibration, which means
that manual recalibration is not required during the
lifetime of the transmitter.
Temperature sensors
The unit has built-in 0…10 V and PT1000 temperature
sensors, working range 0...50°C.
Note! The PT1000 sensor is not compensated for internal
warm-up. The passive temperature output must be
calibrated with a controller.
Supply voltage
The transmitter uses a supply voltage of 24 V AC ±10 %,
50...60 Hz or 15...35 V DC. It automatically detects and
adapts to the supply voltage connected.
Display (-D models)
Display models have an LCD display showing carbon
dioxide concentration and temperature in an alternating
series.
Applications
The carbon dioxide level gives a direct indication of the
indoor air quality. This information can be used to control
ventilation with high precision and improve the air
quality. By increasing the supply air only when necessary,
it is possible to minimise energy costs.
The transmitter is especially suited for environments such
as cinemas, schools, hospitals, conference rooms, assembly
halls, etc.
revision
07 2017
Short facts about CTRT2A
• Output signal CO
2
, 0...10 V DC referring to
0...2000 ppm
• Temperature sensors, 0...10 V DC referring to
0...50°C and PT1000 class DIN B
• CO
2
concentration, 0...2000 ppm
• Temperature, 0...50°C
• Good long-term stability