Zone central control
A zone central control macro (ZCCM) is used to describe a coordinated custom control strategy for zone devices. An example of this is when the heating is switched off as soon as a window is opened. By default, devices have local control loops that independently strive to keep a requested setpoint, i.e. the heater will try to heat even if the room is chilled by an open window.
To define a custom zone control strategy, select "New" in "Controller" field (in the zone’s advanced form). This will open a new ZCCM.
To edit an existing ZCCM, select it in the "Controller" field and click the "Controller" link.
A new ZCCM does not contain any control system. It contains only proxy objects that denote signal sources and control targets. The user must define a control algorithm by inserting appropriate models and connecting them (see Modeling about editing macro objects).
A ZCCM is able to send two types of signals to controlled devices: setpoints and direct actuator signals. Setpoints are used by a local device controller to know what to strive for; a direct actuator signal governs a device directly, e.g. an opening ratio. If the signal is 0.5, the window will be 50% open, independent of conditions in the zone.
The default control target in the template macro, named ‘Central zone control’, transmits direct actuator signals. If for example a signal is connected to the Heating interface of the control target, the name ‘Central zone control’ appears on the list of selectable controllers of any heating device, e.g. a water based radiator.
It is also possible to receive the transmitted actuator signal in a custom made local device controller. In this case, a proxy (receiver) of the Central zone controller must be manually inserted into the local device control macro. Drag the appropriate object from the palette page Links
If, on the other hand, a target for setpoint signals is dragged from the Links palette to the ZCCM and a signal is connected to one of its interfaces, e.g. THERMOSTAT_MIN, all heating device controllers will be striving to reach this target (unless they have custom built controllers with a different agenda). This way, it is for example possible to implement more complex night setback methods than the time scheduled setpoint that is available by default (in the Controller setpoints object).
The ZCCMs are shared between zones (i.e. a control defined in one zone is available in all zones. They are included in the list of IDA Resources. Use this list to manage the controls (e.g., copy to other systems).
A user-defined control macro is never simulated in its original form. Instead, a copy of this macro is created for every zone that uses it and all these individual copies are simulated, with setpoints and input signals local to each zone. Therefore the user-defined macro will never contain results of simulations (such as values of variables in models and time series in output files). To see the actual result, look at the instances of the control macros at advanced level.
