Rehau Reh ta3 User manual

INSTRUCTIONS

Intelligent Room Sensor - Wired

English

Product programme

REH TA3 Room sensor with temperature adjustment

REH TM3 Room sensor with temperature adjustment and mode switch (Auto,

Day, Night, Frost Protection)

REH TD3 Room sensor with temperature adjustment, mode switch (Auto, Day,

Night, Frost Protection) and floor limit sensor

Mounting of 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

BR 1026A11a

Fig. 2

BR1026A01a

Room 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.

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 – .

67338 02/15 (HKT)

• English

Fig. 3 Sensors connected in star formation

BR935A03A

Fig. 4 Sensors connected in bus mode (daisy chain)

BR935A03A

Setting up which room sensor is paired with which thermal actuator

(fig. 5)

Each unit can be set to operate a specific output which in turn controls a

thermal actuator on the manifold. A selector can be accessed under the

front cover of the unit where the number of its output (i.e. its channel no.)

can be set with a screwdriver.

Please note that channels 10 to 14 are marked as A through E on the

selector.

A unit set to CH1 will activate the thermal actuator connected to output 1

on the master. The channel number can be set before power is connected

to the system.

The channel set on the unit can be subsequently changed if needed.

If two units are placed in the same room and set to the same channel,

temperature will be controlled by the average of the temperature recorded

by both units.

Fig. 5

BR1025A05a

Mounting of floor limit sensor (fig. 6)

REH TD3: Floor limit sensor

Units with floor limit sensor have a mechanical jumper on the printed circuit

board allowing limits to be set for MIN. or MAX. temperature regulation. If set for

MAX., the limit setting will be 27°C. If set for MIN., the limit setting will be 17°C.

These temperatures are fixed when used with REHAU BA3 masters unless the

unit has been allocated to a zone group controlled by a REH CT3 room controller.

In this case, the limit settings can be increased or decreased via the room

controller. The limits then set will apply to all relevant room sensors with floor

limit sensor belonging to that group. If a REHAU FC-BMS3 master is used, the

limit settings can be changed using the programming buttons on the master.

Fig. 6

BR1026A04a

Jumper connected: max. limitation

Jumper removed: min. limitation

Jumper location, see fig. 5.

Max. temperature limitation is used to prevent the floor from becoming

too warm. This may be required if special floor surfaces (e.g. solid wood)

are used. The sensor should be positioned where it can read the true

temperature of the floor and should always be within the heated area.

Min. temperature limitation is used to keep the floor surface warm,

irrespective of room temperature. In tiled bathrooms or pool areas, for

example, water will dry more quickly if the floor surface is kept warm. The

sensor should be positioned where it can read the true temperature of the

floor and should always be within the heated area.

To ease replacement, we recommend that all floor sensors are mounted

in a tube positioned between two heating pipes. The inner end of the tube

should be sealed, and the floor sensor cable led back to the bottom of

the wall. If required, the sensor cable can be extended up to 30 m with

standard installation cable.

REH TM3: Use of external room sensor

A remote room sensor can be used instead of the built-in sensor by

connecting the jumper across the two-pin bridge on the printed circuit

board beneath the room sensor cover. From the factory, the jumper is

“parked”on one pin. Jumper location, see fig. 5.

Jumper connected: External room sensor

Jumper removed: Built-in room sensor

See the Installation Manual for further instructions.

Maintenance

The unit is maintenance free.

Keep the air vents (openings) on the unit clean and unobstructed at all

times.

Certications

CE marking

REHAU Limited hereby declares that the product conforms with the following

Directives of the European Parliament and of the Council:

• CE marking: 1993/68/EEC

• EMC - electromagnetic compatibility: 2004/108/EC

• RoHS - restriction on the use of certain hazardous substances: 2011/65/

• WEEE - waste electrical and electronic equipment: 2012/19/EU

Applied standard(s)

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

Disposal and recycling

Recycling of packaging

Protect the environment by disposing of the packaging in accordance with

local regulations for waste processing.

Disposal of the product

Equipment containing electrical components must not be

disposed of together with domestic waste.

It must be collected separately along with other electrical and

electronic waste according to local and currently valid legislation.

Technical Specifications

Purpose of control..................Wired electronic room sensor for controlling

hydronic floor heating and cooling

Connection type ................................2-wire, 5 V, communication bus

Cable type ...............................Standard installation cable ≥0.25 mm²

Cable length ...................Up to 300 m with max. 100 m between two units

Control principle ..................................................PI or ON/OFF

Ambient operating temperature ........................................0/+40°C

Floor limit sensor .....................................................Max. 30 m

Power drain .............................................................<1 mA

Temperature adjustment ..................................................±4°C

Functions REH TA3................................................... None

REH TM3, REH TD3........Auto, comfort, setback, frost protection

Room sensor ...........................................................Internal

Floor limit sensor

REH TA3, REH TM3......................................... None

REH TD3 ........................................Incl. floor sensor

Mounting method..................For mounting direct on wall or in wall socket

Enclosure rating ...........................................................IP 21

Dimensions .........................................H/86.0, W/86.0, D/25.5 mm

REHAU Limited

Hill Court, Walford, Ross-on-Wye, Herefordshire, HR9 5QN

Tel: +44 1989 762600 · Fax +44 1989 762601

[email protected] · www.rehau.uk

Our verbal and written application engineering advice is based upon experience and the best of our knowledge. However it is to be regarded as non-binding information. Working

conditions and use under conditions for which the product was not intended and over which we have no influence exclude any claim resulting from our information. We recommend

that a suitable check is made as to whether the REHAU product is suitable for the envisaged purpose. Application, use and processing of the products is carried out beyond the scope

of our control and are therefore carried out exclusively at your own responsibility. If liability should still apply, then this is restricted, in the case of all damage, the value of the goods

supplied by us and used by you.

Our warranty applies to the consistent quality of our products as per our specification and in accordance with our general terms and conditions of delivery and payment. This document

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