Rehau REH CT3 Instructions

I N S T R U C T I O N S
Intelligent Room Controller/Sensor
67337 02/15 (HKT)
Product programme
REH CT3 Wired room controller with clock
REH DT3 Wired room sensor with temperature adjustment, mode switch
(Auto, Day, Night, Frost Protection) and floor limit sensor
Mounting of room controller/sensor (figs 1 and 2)
The unit is used for comfort temperature control in rooms. The unit should
be mounted on an internal wall approx. 1.4-1.7 metres above the floor in
such a way as to allow free air circulation around it. Draughts and direct
sunlight or other heat sources must be avoided.
Fig. 1 Removing the front cover
Fig. 2
REH CT3 / REH DT3: Wired room controllers/sensors – bus connection
(figs 3 and 4).
Only REHAU units which are suitable for two-wire communication can be used.
Standard installation cable of minimum 2 x 0.25 mm² can be used. Units can
be connected in conventional star formation or in bus mode (daisy chain). The
master has four sets of terminals marked SENSOR/CONTROLLER BUS that can be
used for connecting the 2-core signal cable from the unit.
English
• English
Any unit can be connected to any pair of terminals. The total length of the 2-wire
system can be up to 300 m with a maximum length of 100 m between any two
units. For further information see the table below.
Remember to connect + to + and – to – .
Table: Length of cable
Standard cable Max cable length from
Master to Room Controller/
Sensor with display
≥0.25 mm² Up to 100 m *
≥0.50 mm² Up to 200 m *
≥0.75 mm² Up to 300 m *
*) Up to 300m if operation without backlight is acceptable.
Fig. 3
Fig. 4
© 2015 OJ Electronics A/S
Max cable length from
Master to Room Controller/
Sensor without display
Up to 300 m
Up to 300 m
Up to 300 m
1