ABB i-Bus® EIB/KNX ABB Powernet EIB/KNX

ABB i-bus ® EIB/KNX
ABB Powernet EIB/KNX
LEANtouch (monochrome),
SMARTtouch (monochrome, colour)
Type: 6x36/30M…, 6x36/100x…, 6x36/100CB…
so, a 2-byte temperature value must
be sent to the object “Base setpoint”.
The setpoint temperature can be
changed manually via the rocker buttons
on the panel display. The parameters
“Area for manual setpoint setting”,
“Maximum increasing of setpoint
at heating” and “Maximum lowering of
control value at cooling” determine
the scope for modifying the setpoint. If
a new telegram is sent to the communication
object “Base setpoint” after a
manual setpoint adjustment, the manual
setpoint adjustment can also be
reversed.
Heating/cooling
To be able to address the various controller
types for heating or cooling
mode, the room thermostat can be parameterised
as a continuous or switching
controller. In the case of a switching
controller, it is possible to choose
between a PWM controller (“PI controller”)
and a “Two-position controller”.
In the case of a continuous control response
and a switching PWM controller,
the preset control parameters regarding
the installation type of the
heating or air conditioning system can
be used. If other control parameters
are needed, they can be set individually
via the free parameterisation
option. This option should only be
used if the user has sufficient experience
in control technology.
The continuous controller sends its
control value to a 1-byte object. Electromotive
or electrothermal drives
which are connected to heating actuators
with PWM control can thus be
controlled.
To prevent unnecessary bus loads, it
is possible to set by how much the
control value must change in order to
be sent on the bus. The setting is carried
out as a percentage. The sending
of the control value is preset by a cyclic
period, provided it has not been
modified. This cycle time should not
be set too low (e.g. every 10 min).
In the case of a switching PWM controller,
the output value of the controller
(0...255) is converted into an ON/OFF
ratio. If e.g. a control value of 70%
should be issued, the ON time is 7
min and the OFF time is 3 min at a
preset cycle time of 10 min. The dynamic
range can also be limited in the
same way as a continuous controller.
The parameters “PWM cycle is 0% up
to control value” and “PWM cycle is
100% up to control value” are used for
this purpose. If e.g. a maximum control
value of 80% is set, the controller automatically
sends the value 255 when
a control value of 204 is exceeded.
(See also the diagram below)
To optimise the control characteristics
of the heating or cooling system, the
“Cycle time of the control value” can
be set. To set the correct cycle time,
the type of heating or cooling as well
as the valve drive used should be taken
into account. The following recommendations
can be used:
a)Electrothermal valve drive:
To fully open an electrothermal val-
Output
Control value
100%
80%
20%
0
0
20% 80% 100%
Internal control
value of cont.
controller
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