TA CORA-HKT User manual

1
Radiator thermostat
The radiator thermostat CORA-HKT serves to regulate the flow of radiators, floor heating, wall heat-
ing and such.
Table of contents
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Wireless system. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Relaying wireless signals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Wired connection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Battery powered operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Initialisation run . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Button . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Opening the device . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
LED status indicator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Output variables. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Error codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Input variables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Programming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Device information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Measurements in mm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Technical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Technische Alternative RT GmbH CORA-HKT
A-3872 Amaliendorf, Langestraße 124
Tel [phone] [email protected] Vers. 1.00


2
Installation
Suitable for installation on valves of radiators, floor heaters etc.
For correct measurement of room temperature, horizontal installation of the CORA-HKT is recom-
mended.
In relation to power supply and data transmission, 3 options are available.
1. Battery powered, wireless data transmission
2. 12V wired power supply, wireless data transmission
3. 12V wired power supply, wired data transmission via CORA-DL
The thermostat can only be operated using one of these options. It can also only be connected/cou-
pled with a single controller at a time.
When programming on a controller using the CORA-HKT, it is necessary to enter whether wired or
wireless data transmission is in use.
When using wired 12V power supply, values are updated every minute. When battery powered, val-
ues are updated every 5 minutes.
If the CORA-HKT is powered using batteries, it cannot be used as a HOP node (see „Relaying wireless
signals“).
Wireless system
Principles
The wireless system comprises multiple CORA devices (e.g. CAN-MTx2 and CORA-HKT), which com-
municate with one another, exchange data or transfer firmware.
The wireless range is around 1000 m outdoors, and typically 30 m in buildings (through approx.
2 walls/ceilings, depending on thickness and material). Up to 3 additional wireless devices can be
used as a bridge to enable data to be exchanged under deviating conditions.
RCV-DL, GBS-F and RAS-F devices cannot be used.
Pairing CORA devices
Two steps are carried out to pair two devices:
1. Allow pairing on the target device
2. Initiate pairing on the control device
To allow pairing on the EHS-R (= target device), double click on the button on the casing (= 2 click
within 2 seconds). Pairing is then allowed for 5 minutes (see chapter "Reset / Pairing").
On the control device, the CORA ID for the CORA-HKT is required for pairing.
The pairing process on other devices (control device) can be found in the corresponding operating
instructions.
Relaying wireless signals
Wireless-capable devices can relay signals of other devices. All required settings for this are carried
out at the device, which transmits the signal to be relayed.
The CORA-HKT can also be used to relay wireless signals of other devices, but only when used with
wired power supply. Should it receive signals for relaying, it does so automatically. No additional set-
tings for the CORA-HKT are necessary for relaying signals.

3
Wired connection
The CORA-HKT can either only be supplied with power using wires (12V), or it can be supplied with
power and transmit data using wires (CORA-DL). Ensure correct polarity of the DL bus.
For either case, the CORA-HKT offers an option to lead wires out of the device‘s casing.
Battery powered operation
The HKT can be powered using 2 AA batteries (not included).
When battery powered, the following is true:
• The HKT cannot be used for relaying wireless signals (HOP).
• Values are updated every 5 minutes.
• Battery lifetime varies based on activity, but typically lasts 3 years.
Initialisation run
As soon as the HKT receives power, it immediately carries out an initialisation run. As such, it should
already be installed when power is supplied. If this was not the case, a restart via button press should
be carried out after installation (see „Button“)
Process of initialisation run:
1. The HKT opens the valve fully.
2. The HKT begins closing the valve until it detects the valve‘s pin through its resistance (this
defines the position of 100%).
3. The HKT goes to position 0% (fully closed).
The surface marked in
red can be broken off to
lead wires through the
gap.
+12V
GND
DL
+
+–
–

4
Button
On the inside of the device, a button is located, used for coupling, restarting etc.
Opening the device
By pressing along the cover (as shown in the picture) it can be opened alongside the device.
LED status indicator
The LED indicates the status of the device.
Button press Function
1 brief press Restart
2 brief presses Allow coupling for 5 minutes
10 sec long press Total reset
While holding the button for a total reset, the LED
flashes red. The button must be held until the
LED turns green, at which point the total rest is
carried out.
Green, flashing quickly The button has been pressed twice – wireless coupling is allowed
for 5 minutes (the LED only flashes for the first three seconds, not
the entire 5 minute duration).
Orange flash every 10 sec Valve could not be detected (error code 4)
Red flash every 10 sec Battery charge <5%; the motor is no longer actuated
status LED

5
Output variables
The following values are sent from the CORA-HKT to the connected device (not changeable):
Error codes
Every error state has a number assigned to it. The sum of the codes of all active errors is displayed
under „error code“.
Example: An error code of 6 means that errors 2 and 4 are active.
Timeout Digital value Yes/No (Yes, if connection lost)
Battery charge Battery charge 0-100%
Eff. room temp. The room temperature used for calculations.
• If a value is connected to room temp. , that value is output here.
• If no value is connected, the measured temperature ( HKT room temp. ) is
output.
HKT room temp. The room temperature is estimated based on two internal sensors.
Current position Current position of the thermostat motor 0% = fully closed
100% = fully opened
The „fully opened“ position is defined by the initialisation run (see page 3),
„Fully opened“ depends on the valve of the radiator.
Window contact
Digital value Yes/
No (Yes = win-
dow closed)
Based on the room temperature (always according to internal sensors), the
device tries to detect the opening of a nearby window.
If the room temperature drops...
• by 0.2°C every minute over a span of 3 minutes
•or by 0.5°C over the span of one minute
the window contact switches to No (= window open)
To switch back to Yes (= closed) the temperature has to rise
• by 0.1°C every minute over a span of 3 minutes
•or by 0.25°C over the span of one minute
The window contact always switches back to Yes (= closed) 60 minutes after
initial opening.
Error code If a malfunction of the CORA-HKT is detected, the appropriate error codes are
displayed here.
1Battery charge low (<5%)
2An error occurred during actuation of the motor.
4Valve not found during initialisation run or initialisation run failed due to low battery.

6
Input variables
The following values can be sent to the CORA-HKT (not changeable).
Room temp.
[°C]
The current room temperature can also come from an external sensor. Help-
ful in case the HKT‘s own measured temperature is not reliable.
Set room temp.
[°C]
The target room temperature the HKT should aim for.
Heating
digital [On/Off]
If On:
0% = fully closed
100% = fully opened
If Heating and Cooling are On simultane-
ously, the valve will be opened fully.
If both are Off simultaneously, the valve will
be closed fully.
Cooling
digital [On/Off]
If On:
0% = fully opened
100% = fully closed
Set position
[0-100%]
The desired position of the valve can be set manually. Helpful in case several
HKTs in the same room regulate different radiators. See programming exam-
ple on page 7.
Begin decalcifi-
cation
pulse
Every two weeks, the valve is opened fully, flushed with water for roughly 5
seconds, closed fully and then returned to set position. This serves to decal-
cify the valve.
Through a pulse, the decalcification process can be started manually to pre-
vent automatic decalcification at an undesired time. The manual start of the
process resets the timer for the automatic process.
The „fully opened“ position is defined by the initialisation run (see page 3), „Fully opened“
depends on the valve of the radiator.

7
Programming
The CORA-HKT must be added to the programming of the connected controller. We recommend us-
ing the PC software TAPPS2 for this purpose. It is available to download for free at www.ta.co.at/
en/download/software/
In TAPPS2, the CORA-HKT has a designated block under CORA devices:
A typical use case would be the connection with the output variable Effective set room temp. of a
Heating circuit control or Individual room control function.
Several HKTs in the same room
If several HKTs are installed in the same room, measurement inaccuracies can lead to the thermo-
stats attempting compensate for each other‘s temperatures by setting the valves into opposite po-
sitions (one HKT might heat excessively while the other might not heat at all).
Several HKTs in the same room should therefore be coordinated in the programming.
Example: Three HKTs, one receives the Set room temperature from an Individual room control func-
tion and forwards its own set position to the other HKTs.
Device information
On the controller, under CORA devices > Radiator thermostat > parameters > device information,
various details are available.
„Device type“ denotes the type of power supply, either „HKT 12V“ or „HKT battery“.
The „master“ should be whichever
HKT measures the room tempera-
ture most reliably (or receives it
from an external sensor).

8
Measurements in mm
Technical data
Subject to technical modifications as well as typographical and printing errors. This manual is only
valid for devices with the corresponding firmware version. Our products are subject to constant tech-
nical advancement and further development. We therefore reserve the right to make changes without
prior notice. ©2023
Batteries 2x AA (not included)
Battery lifetime varies based on batteries and motor activity, typically 2 years
Bus load CORA-DL 5%
12V Power consumption based on motor activity max. 3 W (when idle, typically 0.1 W)
Screw M30x1.5 fine thread
Permissible surround-
ing temperatures 5 - 45°C
94
48
50

9

10

11
EU Declaration of conformity
Document-Nr. / Date: TA21024 / TBA
Company/Manufacturer: Technische Alternative RT GmbH
Address: A-3872 Amaliendorf, Langestraße 124
This declaration of conformity is issued under the sole responsibility of the manufacturer.
Product name: CORA-HKT
Product brand: Technische Alternative RT GmbH
Product description: Wireless radiator thermostat
The object of the declaration described above is in conformity with Directives:
2014/35/EU Low voltage standard
2014/30/EU Electromagnetic compatibility
2011/65/EU RoHS Restriction of the use of certain hazardous substances
2009/125/EU Eco-design directive
Employed standards:
Position of CE - label: On packaging, manual and type label
Issuer: Technische Alternative RT GmbH
A-3872 Amaliendorf, Langestraße 124
This declaration is submitted by
Dipl.-Ing. Andreas Schneider, General manager,
This declaration certifies the agreement with the named standards, contains however no warranty of
characteristics.
The security advices of included product documents are to be considered.
EN 60730-1: 2011 Automatic electrical controls for household and similar use – Part 1: General
requirements
EN 61000-6-3: 2007 Electromagnetic compatibility (EMC) - Part 6-3: Generic standards - Emission
standard for residential, commercial and light-industrial environments+A1: 2011
+ AC2012
EN 61000-6-2: 2005 Electromagnetic compatibility (EMC) - Part 6-2: Generic standards - Immunity
for industrial environments+ AC2005
EN 50581: 2012 Technical documentation for the assessment of electrical and electronic prod-
ucts with respect to the restriction of hazardous substances
EN 300220-2:2017-05 Short Range Devices (SRD) operating in the frequency range 25 MHz to 1000
MHz - Part 2: Harmonised Standard covering the essential requirements of arti-
cle 3.2 of the Directive 2014/53/EU for non specific radio equipment (Endorse-
ment of the English version EN 300 220-2 V3.1.1 (2017-02) as German
standard)
EN 301489-1:2017-07 Electromagnetic Compatibility (EMC) standard for radio equipment and services
- Part 1: Common technical requirements
EN 301489-3:2019-08 Electromagnetic Compatibility (EMC) standard for radio equipment and services
- Part 3: Specific conditions for Short-Range Devices (SRD) operating on fre-
quencies between 9 kHz and 246 GHz


12
Warranty conditions
Note: The following guarantee conditions do not limit the legal right to a warranty, but rather expand
your rights as a consumer.
1. Technische Alternative RT GmbH provides a one year warranty from the date of purchase
for all the devices and parts which it sells. Defects must be reported immediately upon
detection and within the guarantee period. Technical support can supply the correct solu-
tion for almost every known problem. In this respect, contacting us immediately will help to
avoid unnecessary expense and effort in troubleshooting.
2. The guarantee includes free repair (but not the cost of on-site fault finding, removal, refit-
ting and shipping) due to operational and material defects which impair operation. In the
event that a repair is not economical in the opinion of Technische Alternative for reasons
of cost, the goods will be replaced.
3. Not included is damage resulting from the effects of a voltage surge or abnormal ambient
conditions. Likewise, no liability can be accepted if the device defect is due to: transport
damage for which we are not responsible, incorrect assembly and installation, incorrect
use, failure to observe the operating and installation instructions or incorrect maintenance.
4. The guarantee will become void if repairs or actions are carried out by people who are not
authorised to perform them or have not been so authorised by us or if our devices are oper-
ated with spare parts, auxiliary parts or accessories that are not considered to be original
parts.
5. The defective parts must be returned to our factory with a copy of the proof of purchase
and a precise fault description. Processing is accelerated if an RMA number is requested
via our homepage www.ta.co.at. The defect must be clarified with our technical support
beforehand.
6. Services provided under guarantee result neither in an extension of the guarantee period
nor in a commencement of a new guarantee period. The guarantee period for fitted parts
ends with the guarantee period of the whole device.
7. Further or other claims, especially those for compensation for damage other than to the
device itself, insofar as a liability is not legally required, are excluded.
Legal notice
These installation instructions are protected by copyright.
Use outside the copyright requires the consent of Technische Alternative RT GmbH. This ap-
plies in particular to reproductions, translations and electronic media.
Technische Alternative RT GmbH
A-3872 Amaliendorf, Langestraße 124
Tel.: [phone] Fax [phone]
E-Mail: [email protected] --- www.ta.co.at --- ©2023