Controller - ABB i-bus KNX Product Manual

4.3

Controller

© 2009 Busch-Jaeger Elektro GmbH – A Company of the ABB Group
The ambient temperature controller can be used for heating only, cooling
only or for heating and cooling.
If the ambient temperature controller is to be used for heating and cooling,
it can switch automatically from heating to cooling and cooling to heating.
The controller automatically detects whether it must send a control value
for heating or cooling. If automatic switching is not wanted, switching
between heating and cooling can be done by an external, central controller
using the 1-bit object "switchover heating/cooling. In this setup, the heat and
cooling icons are continuously displayed in the respective mode. The object
is enabled by the parameter "switching between heating and cooling".
The control value that is sent for heating and/or cooling can be sent on
a common communication object "control value heating/cooling" or two
separate communication objects "control value heating" or "control value
cooling". If a common object is used, it may be necessary to inform
the actuator whether the control value refers to heating or cooling.
The parameter "switchover between heating and cooling" can be enabled
with the setting "automatic and send" a 1-bit communication object
"switchover heating/cooling". If heating operating mode is enabled, a "1"
is sent to the bus and if cooling operating mode is enabled, a "0" is sent.
A common communication object for heating and cooling is required to
actuate 2-pipe systems, i.e. heating and cooling modes use the same pipes.
Two single communication objects are used in 4-pipe systems, which have
separate pipes for heating and cooling.
The parameter "number of output channels" defines whether an object
("1 channel (2-pipe system) for heating and cooling") or two objects
("2 channels (4-pipe system) for heating and cooling") are to be shown.
Separate control types can be parameterised for heating and cooling.
One of the following control types can be selected:
- 2-point
- PWM
- continuous
- Fan Coil
The individual control types are described below in more detail.
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