abb i-bus knx raumklimatisierung
TRANSCRIPT
• Welcome to the ABB i-bus KNX training programme from ABB STOTZ KONTAKT.
In this module you will learn about room climate control with ABB i-bus KNX. If you
need help navigating through this module, please click the Help button. To view the
presenter notes as text, click the Notes button in the bottom right-hand corner. You
can also download this presentation in printable format by clicking the attachment
button in the top right-hand corner.
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• At the end of the first part of this eLearning module we will have detailed
knowledge of
• the capabilities of KNX in heating, ventilation and climate control applications,
• ABB's product range for these applications and
• ABB solutions for individual room heating control and for operating blower
convectors, which are also known as Fan Coil Units.
ABB products and solutions for room climate control will be in the second part of
the unit.
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• ABB i-bus KNX makes it possible to integrate room temperature control, ventilation
and climate control into a networked building infrastructure.
• A modern building can only be operated efficiently when all the technical aspects in
a building (lighting, sun protection, heating- ventilation-climate ) are networked and
work in perfect harmony.
• This applies in particular to the energy efficiency, but also to the management,
maintenance and the flexibility needed when requirements change.
• Most of the energy consumption in a building can be traced back to the climate
control, depending of course on climatic region and season and the different
focuses (heating, cooling, ventilation ) and applications (Fan Coil Unit, hot water
heating, electric heating, air conditioning, cooling systems with activation of
building units etc.).
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• Besides the heating and cooling sources themselves, artificial light and natural light
also affect the room temperature.
• People and electrical devices, such as computers, heat the room.
• Although opening windows and doors improves the quality of the air, it also
changes the temperature within the room. Walls, ceilings and windows produce a
thermal exchange with the surroundings and also with adjacent rooms inside the
building.
• The room climate in rooms for living and working plays a role in the health,
efficiency and comfort of the occupants. Besides room temperature, another
decisive factor in determining the indoor air quality and thus the room climate, is
the carbon dioxide content of the air in the room.
• In the following slides we will become acquainted with solutions to this problem
using ABB i-bus KNX.
• Next to lighting control, room climate control is the most important function in
building technology.
• The main application is the individual room control of hot water heating involving
radiators and floor heating or cooling rooms with Fan Coil Units.
• A reliable control system is a prerequisite for the efficient, comfortable use of
buildings.
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• The slide shows the unsatisfactory situation of a conventional thermostat mounted
on the radiator of a hot water heating system.
• For a pleasant room temperature the thermostat is on setting 3.
• The problem is the accuracy. Which setting corresponds to which temperature ?
• If setting 5 is activated because it is too cold in the room, although the valve is
completely open, further control is not possible.
• Normally the user forgets to reset the old value on the thermostat, so it will
probably become too warm in the room and energy is wasted.
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• ABB’s products for KNX offer a wide range of solutions in this area
• such as room temperature controller,
• valve drives with the corresponding actuators,
• Fan Coil actuators for Fan Coil Units and valve actuators, but also special
components such as analogue inputs and outputs and
• air quality sensors for the CO2 concentration of the room.
• Using presence detectors and push buttons, the room temperature can be
controlled as needed and the sensors and actuators work extremely accurately.
• When a window is opened a magnetic reed contact initiates to close e.g. the
radiator valve.
• With a time function various temperature setpoints can be activated at specified
times, which is extremely useful in a bathroom, for instance.
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• We can take a look now at some typical solutions for temperature control with ABB
i-bus KNX. There will be a detailed version of this later in the eLearning module.
In a dwelling a room temperature controller records the temperature and,
specifying a setpoint, transmits a control value to the electronic switch actuator
controlling the thermoelectric valve drive of the floor heating circuit or drives an
electromotor valve on the radiators in the room.
• ABB’s room temperature controller also allow additional heating or cooling to be
activated.
In this room e.g. the floor heating is the basis stage and the radiator is switched on
for more rapid heating of the room when the room temperature is low.
• To save energy, when the window is opened, the window contact initiates closing of
the valve by means of ABB’s universal interface via KNX.
• Other devices on the Bus, such as push buttons or displays, give continuous
access to the control system, e.g. an operating mode switch-over from day to night
mode with a reduced setpoint.
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• In an office the demands on the room climate control are very exacting as, in many
cases, the room must be heated as well as cooled.
A supply of fresh air is also important, but opening a window for ventilation
purposes is often not foreseen.
• The room temperature controller uses a Fan Coil actuator to control the heating or
cooling valve as well as the speed of the ventilation.
• When it is necessary an electric heating unit can also be switched on with a relay.
• A condensation sensor, connected to one of the actuator’s binary inputs, raises the
setpoint on cooling or closes the valve to protect the Fan Coil Unit.
• To save energy a window contact can use the binary input in the Fan Coil actuator
to close the valve. Thanks to the bus technology with ABB i-bus KNX a conference
room in an office building can, for example, be cooled at any time via a
visualisation in the foyer.
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• The same solution can also be achieved in an hotel room with another device, the
Room Master. The Room Master also enables the control of room functions such
as lighting and blind control.
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• Let’s look at the individual components more closely:
• The room temperature controller measures the current temperature in the room
and, on the basis of the setpoint and the control algorithm, sends a control value in
a 1 or 8 Bit format to the Bus.
• The setpoint can be changed in the application, on the device itself or externally
e.g. via a visualisation.
• Besides display options such as setpoint, actual value and operating mode, control
functions are also possible on the device e.g. operating mode switch-over.
Other buttons on the thermostat enable independent functions for lighting and blind
control to be programmed, so that often no other operating elements are needed in
the room.
• ABB offers a variety of components tailored to the existing design lines: solo, triton
and priOn.
• The room temperature controller Fan Coil was designed specifically for use with
Fan Coil Units, with the buttons intended exclusively for room temperature
functions.
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• Here we have an overview of the actuators, in other words, devices for controlling
valves and fan motors. First, the components used for valves :
• Electronic switch actuator ES/S with thermoelectric or motorised valve drive
• Valve drive actuator VAA/S with thermoelectric valve drive
• Electromotor KNX valve drive ST/K
• Universal interface with electronic relay and thermoelectric valve drive
• There are also KNX devices which are deployed for use with Fan Coil Units, in
other words, which can control both valve actuation as well as multi-speed fans :
• Room Master RM/S
• Fan Coil actuators LFA /S and FCA/S
• Room Controller RC/A
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• Besides the thermoelectric valve and the electromotor KNX drive there are also
motorised valve drives without KNX-interface, the so-called 3-point valve drives.
• These are controlled by two independent contacts, whereby the Fan Coil actuator
FCA/S 1.1M and the Room Master RM/S already have the appropriate software
and hardware.
• Another motorised valve drive on the market is driven by a 0…10 V signal.
• For this we have ABB's Fan Coil Actuator FCA/S 1.2.2.1.
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• To further our understanding and to learn how to select the different valve drives
we can now examine the operating mode, particularly the aspects of control and
behaviour. An actuator for controlling electrothermal valve drives can only work
digitally, in other words, it is either on or off. This is a 1 Bit signal. A 2-step control
can be configured in all KNX room temperature controllers.
• After specifying a setpoint and a tolerance band for the room temperature the room
temperature controller will try to control the room temperature by switching off and
on, in other words by opening and closing the valve.
• Due to the slow response behaviour of the thermoelectric valve drive the valve
opens or closes slowly, the time between open and closed being 2 to 3 minutes.
• The actual temperature in the room may possibly fluctuate because of the situation
we have just described, but this can be minimised by decreasing the temperature
limits and tolerance band.
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• Another setting often used in the room temperature controller is the pulse width
modulation PWM. which also works with thermoelectric drives and their switch
actuators.
• During an adjustable cycle time of e.g. 15 minutes the room temperature controller
opens and closes the valve for a specified time, depending on the control value
calculated.
• We can look at a short example: with a cycle time of 15 minutes and a control
value of 60 % the valve is opened for 9 minutes and closed for 6.
• In this case the reaction of the valve is delayed due to the system inertia of the
valve drive and, depending on the power-on / power-off time, the valve is also
perhaps not fully closed or opened. Because of the thermal inertia of the whole
room temperature control system, PWM control is widely-applicable in classic
heating and cooling systems. Its advantages are its low-price, as well as the low-
maintenance and low-noise valve control.
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• Continuous control is activated in the thermostat when the motorised KNX valve
drive or the 3-step valve drive is used.
• In the valve drive the control value calculated is converted rapidly into a direct
positioning of the valve.
In contrast to the 1 bit telegram in 2-step control or in pulse width modulation, this
is an 8 bit value telegram.
While the advantages are the faster, more exact positioning of the valve, higher
investment costs and the drawbacks of a mechanical system must also be taken
into account.
The same occurs when we use the 3-step and 0…10 V valves we mentioned
earlier.
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• What have we learnt so far?
• Climate control integrated into the system KNX is logical and supports the
interaction of all the components and functions
• The principle of individual room heating control and of Fan Coil Actuators for
climate control and an overview of the corresponding ABB sensors and actuators
• Have you understood everything so far ?
If you have, please click ”continue”. If you would like to repeat the topic, please
click “No”
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• At the end of this, the second eLearning module we will have detailed knowledge of
the operating mode of the different valve drives and the corresponding KNX
actuators the functionality of Fan Coil actuators and the capabilities of an air quality
sensor
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• Thermoelectric valve drives are used for radiators, cooling ceilings, floor heating.
• Fan Coil Units and are standard components in room climate control.
ABB offers these valve drives for 230 V- or 24 V-valves in a “Normally closed“
version. The opening and closing time is about 3 minutes.
A wide range of valve adapters is available for the most common valves
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• The functional principle is as follows:
• The expansion element is heated by applying operating voltage of 230 V or 24 V
and expands
• the integrated push rod performs the travel
• the travel (about 4 mm) is transferred to the valve push rod,
• the valve is opened or closed and this can be seen in the function display.
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Switch actuators with electronic relays are used to control thermoectric valve drives.
Switch actuators with mechanical relays can be used, as this application is already
available for this use.
The disadvantage is the noise behaviour as well as the mechanical load on the relay
resulting from the large number of switching operations over the operating period.
Consequently, preference is given to actuators with electronic relays which are noise
and wear-free. ABB offers 2 different electronic actuators, the electronic switch actuator
ES/S and the valve drive actuator VAA/S. With a supply voltage of 24 or 230 V the
electronic relay, a Triac, switches the valve on or off. The number of parallel
connectable thermal valve drives depends on the load current of the devices and must
be taken into account correspondingly. In rooms with several heating circuits and
valves, this means that often only one channel of the actuator per room needs to be
occupied.
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• The electronic switch actuator ES/S comes with 4 or 8 channels.
• And thermoelectric valve drives for 24 or 230 V AC or DC can be connected.
• A plastic foil keypad with LEDs is available for manual operation and status display.
• One special feature of the electronic switch actuator is the provision for connecting
motorised 3-point valves. In this case 2 outputs needed for each valve and the
number of channels is reduced accordingly.
• One channel can also be parameterised as a normal switching channel. This
means that a noise and wear-free switch relay up to 1 A load current is available for
special applications.
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• The valve drive actuators with 6 and 12 channels are an extension to our product
range of thermoelectric valve drives controllers.
• They are a cost-effective solution for thermoelectric valve drives and boast almost
all the functions of the electronic switch actuators we have just met.
• The permitted nominal voltage is between 24 and 230 V AC
• The maximum nominal current per output is 160 mA which normally drives a
maximum of two valve drives parallel to an output.
• Please do not forget: the device is has been designed for thermoelectric valve
drives, it is not possible to operate motorised 3-point valve drives or the switch
actuator function.
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• Since the electromotor valve drive ST/K 1.1 as an KNX component is connected
directly to the Bus, installation is simple and rapid. The main advantage is the fast
control with exact positioning of the valve. However the potential noises resulting
from the mechanical parts of the valve drive must also be taken into account.
• Another feature are 2 integrated binary inputs where window contacts or even
conventional presence detectors can be connected.
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• The electromotor valve drive ST/K 1.1 is mounted directly on the valve with the
appropriate mechanical adapter, power is supplied by the bus, so the installation is
quite straightforward.
• The automatic valve travel detection aligns the device to the actual stroke of the
valve, which ensures safe operation.
• 5 LEDs show the actual position of the valve, which is extremely useful for
commissioning and diagnostic purposes.
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• One other important component in room climate control is the blower convector,
which is also known as the Fan Coil Unit.
• This is used mainly in cooling applications but also for heating purposes and is
actually a heat exchanger.
Hot or cold water from a central supply is controlled by a valve.
• A step-regulated ventilator circulates the air in the room past the low-noise heat
exchangers and the room temperature changes.
• If a building is usually cooled and only rarely heated, it is often not worth installing
hot water heating with a Fan Coil.
• In this case electric heating can be integrated into the Fan Coil, which is activated
by a switch actuator. The room temperature is raised using the 3-speed fan.
• ABB's Fan Coil actuators have the appropriate relay.
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• This chart shows the control value of the room temperature controller with control
of the valve and the fan depending on room temperature and using a Fan Coil
actuator. This is assuming the system is using both the heating and the cooling
mode, and the heating setpoint is 21 degrees, and the cooling setpoint 24 degrees.
In other words, between 21 and 24 degrees there is neither heating nor cooling
being performed, this is known as the dead zone. The valve is driven according to
the red characteristic for heating and the blue characteristic for cooling. The valve
opening is dependent on the control value and is executed by a motorised valve
drive or by pulse width modulation of a thermoelectric valve drive.
• For example, in the cooling mode, if the room temperature is 26 degrees the valve
is set with a 35 % opening and the fan revolves at speed 2.
• The threshold values of the different speed steps can be set in the Fan Coil
actuator software.
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• We can move on to examine the Fan Coil actuators in more detail.
The LFA/S is a Blower/Fan Coil actuator, which not only allows the operation of
Fan Coil Units but also fan control with up to 5 speeds.
• The hardware provides for 6A switch actuators with 4 and 8 outputs, which can be
used as 1-fold actuator for 3-speed fan control (Type LFA/S 1.1) or as a 2-fold
actuator (Type LFA/S 2.1) for two 3-speed fans or as a 1-fold actuator for 5-speed
fan control. Classic manual operation is not foreseen on the device itself.
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• The schematic diagram illustrates the interaction between the Blower/Fan Coil
actuator LFA/S 2.1 and the KNX devices via the communication objects and also
the outputs with their connected loads.
• The first 3 outputs activate the various fan speeds, while the 4th output shows
optional higher-level motor control with a separate relay.
• The thermoelectric valve drives for heating and cooling are connected to the next 2
outputs. These outputs are normally controlled in such a way that with a control
value greater than zero the contact is closed and the valve is opened completely.
Temperature control is then performed exclusively by the fan speed.
Whenever necessary PWM modulation can also be used for approximate
positioning.
• Other free outputs can be used as needed, in this case to connect luminaires.
• One important part is the room temperature controller which communicates mainly
with the Blower/Fan Coil actuator via the control value.
Other optional communication objects, such as status messages or operating–
mode switchover, are also available.
• A KNX button switches the two lighting outputs.
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• The Fan Coil actuator FCA/S 1.1M is a further development of the Blower/Fan Coil
Actuator LFA/S.
• The device has 3 outputs for fan control and a total of 4 electronic outputs for
connecting thermoelectric and motorised valve drives.
• Two binary inputs and a second switching output are also available.
• The plastic foil keypad enables the familiar manual operation und status display.
• The application is based on the functionality of the LFA/S with a number of
enhancements.
• With a commissioning power supply connected to the bus connecting terminal, the
device can also be manually operated without KNX-Bus for testing Fan Coil Units.
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• The diagram shows the inputs and outputs of the Fan Coil actuator FCA/S 1.1M.
While the switching output can be used for example for auxiliary electrical heating,
the binary inputs can be used to connect a window contact or condensation
sensors.
• The outputs for valve drives for heating and cooling are separate. As each channel
has two independent electronic outputs both thermoelectric and motorised drives
can be implemented. This results in low-noise and low-wear but also offers further
options in valve control, as we will see in the following slides.
• In place of electronic outputs the Fan Coil actuator FCA/S 1.2.2.1 offers two 0-10 V
outputs for the corresponding valve. The functionality of this solution is the same
as the one we have just described.
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• One interesting aspect of Fan Coil Unit control is the control of the valve depending
on the control value.
• With the Blower/Fan Coil actuator LFA/S, when the valve is opened at a control
value greater than zero, the temperature control in the room is executed by the
change in fan speed. The valve is only closed when the thermostat sends no more
control values.
• The FCA/S has more options. The standard characteristic has a linear behaviour,
in other words, with e.g. a 30 % control value the valve is also controlled by this
value.
When a thermoelectric valve drive is connected the pulse width modulation (PWM)
is implemented, while for motorised drives the valve can be positioned directly by a
value.
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• Which opportunities emerge when functions are used to adjust or restrict this
characteristic?
First of all, the characteristic can be changed via four adjustable pairs of values for
control value and valve position.
We can look at some practical examples of this :
• If the valve is only opened with a control value of 20 %, the fan runs, but at speed
1, so the room is neither heated nor cooled, only ventilated.
A stronger heating and cooling effect is reached when the valve is completely
opened with a control value greater than 80 %.
• If the valve is opened a minimal 20 % with very small control values, possible
whistling noises can be avoided, caused by small water flow.
If the valve is opened no more than 80 % with higher control values the number of
valve positions can be reduced, because the non-linearity of the valve prevents a
more powerful flow of water.
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• Besides room climate control with heating and cooling the quality of the air is
another parameter for physical comfort in a building, whereby the CO2 content is
particularly crucial. Above a concentration of 1000 ppm the quality of the air falls,
while higher values can cause lapses in concentration or headaches
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• Humidity and, of course, the room temperature are also important. This graph
shows the relationship between the two.
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• This is where air quality sensor comes into action, measuring the CO2
concentration, relative humidity and room temperature. The values measured can
be transmitted to the Bus for further processing or display and other functions can
be carried out when the set values are reached.
• Two LEDs show in different colours in which area humidity and CO2 concentration
are situated, so the user can intervene manually in the control of the functions
mentioned
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• In this overview we can see the interaction of the air quality sensor with different
KNX devices:
• The central device is the air quality sensor which measures the CO2 concentration,
the relative humidity and the room temperature.
• When set thresholds are exceeded or underrun logically linked actuators can
perform functions such as increasing the fan speed or opening or closing a
ventilation flap or window to increase the supply of fresh air.
• Independently of the air quality sensor, higher-level KNX components, such as
pushbuttons, presence detectors or timer modules can of course influence the
functions we have just examined
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What have we learnt so far ?
• The operating principle of the thermoelectric valve drive with KNX actuators with
electronic outputs
• The differences between an electronic switch actuator and a valve drive actuator
• The alternative motorised valve drive as a direct KNX device
• The properties of Fan Coil actuators LFA/S and FCA/S with the options
• of characteristic curve adjustment in the FCA/S
• The new opportunities offered by the use of the air quality sensor LGS/A 1.1 in a
KNX installation
Have you understood everything so far ?
If you have, please click ”continue”. If you would like to repeat the topic, please click
“No”
• Thank you very much for taking this first unit of the eLearning course about room
climate control. We hope that this course has been interesting and helpful in
extending your knowledge of room climate control, the technologies involved and
their areas of operation.
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