Technical Manual Temperature Controller
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48
4.5.6.3 Switchover heating and cooling
B the setti g heati g/ ooli g s it h o e it is possi
ble to adjust whether the controller shall
switch automatically or via communication object. At the automatic switchover, the controller
evaluates the setpoints and knows because of the adjusted setpoints in which mode the controller is
at the moment. When the controller heated before, the controller switches over when the measured
temperature rises over the adjusted setpoint for cooling. As long as the controller is at the dead zone
between heating and cooling, the heating process remains set, but does not heat as long as the
temperature is above the adjusted setpoint for heating.
By choosing the switchover via object, an additional communication object is shown. By this object
the switchover can be done. The controller stays as long at the adjusted operating mode until it
becomes a signal via the according communication object. As long as the controller is at the heating
mode only the setpoint for the heating is watched, also if the controller is, according to its setpoints,
already at the cooling mode. A start of the cooling mode is also only possible, when the controller
becomes a signal via the communication object.
A
s it hes the heati g p o ess o a d a
s it hes the ooli g p o ess o .
The following chart shows the relevant communication object:
Number
Name
Length
Usage
17
Heating/Cooling switchover
1 Bit
Switchover between heating and cooling
1=heating; 0=cooling
Table 39: Communication object heating and cooling
