REG SYSTEM ARCHITECTURE

The REG System divides the management of the system into several subsystems, represented in this diagram to be kept in mind while programming the controller:

Each subsystem shows parameters through which it is possible to manage and customize the control logic:

Zones control the temperature (and, if required, the humidity) of individual parts of the system; up to 32 zones can be managed;
Timetables allow the weekly operating programs to be set; up to 8 timetables can be managed by the system;
The Global Setting subsystem groups the parameters that have an effect on the whole system, for examples the system ON/OFF and the current season (Summer or Winter);
Dehumidifiers control the system’s dehumidifiers; up to 8 dehumidifiers, integration or ventilation units can be managed by the system;
Circuits control the Direct or Mixed circuits (water pumps, mixing valves and flow probes); up to 8 circuits can be managed by the system;
The DHW controls the Domestic Hot Water production;
The Solar Panel Management allows the control of one or two Solar Thermal System for DHW production or heating integration;
Sources allow to manage up to 3 heating/cooling sources (boilers, thermal fireplaces, heat pump, chillers, etc.);
The OpenTherm/Cascade subsystem is a special type Source, with which it is possible to manage from 1 to 8 generators in cascade.

For some subsystems (as DHW and Global Settings) there is only one exemplar, while in most of them there are multiple exemplars (or “instances”) of the same subsystem: e.g., there are 32 subsystems of “Zone” type, 8 subsystems of “Timetable” type, and so on (the number in brackets in the above diagram shows how many exemplars of each subsystem are available).

Each type of subsystem is dedicated to the processing of a specific aspect of the thermoregulation.

The “programming” of REG System consists of:

Activating the type and the number and the subsystems required to regulate the system.
Setting the individual systems through the parameters that each of them makes available.
Linking the subsystems together to combine their functions in the way required to set the system.

Moreover to the various subsystems dedicated to the regulation of a specific part of the system (Zones, Circuits, etc.), there is a “Global Settings” subsystem, whose parameters influence all the other subsystems.

To understand how the various subsystems need to be configured and linked together for the management of a specific system, it is essential to know the basic functions of each subsystem.

Global Settings

The Global Settings subsystem manages certain functions that have an effect on all other subsystems and therefore on the REG System as a whole.

The main states determined by the Global Settings subsystems are:

Global System Activation, that determines if the Zones assigned for heating and/or cooling (excluding the Zones configured for DHW and CMV) are active or not.
Current Season, SUMMER or WINTER, that determines the behavior of all other subsystems.
Global DHW Activation, that determines if the DHW subsystem is active (it also determines the activation of potential Zones configured as DHW function).
Global CMV Activation, that determines if the ventilation function of the Dehumidifiers is active.

For further details see SYSTEM ACTIVATION AND SEASONAL CHANGE.

Timetables

Timetables allows weekly programs to be defined; timetables function is to determine, for the subsystems to which they are connected (that may be Zone, DHW, or CMV function), the current Working Mode.

The concept of Working Mode is recurrent in the REG System: Working Mode determines some fundamental aspects of certain subsystem operation; for examples, in the case of Zones, the Working Mode determines the temperature set point and other aspects; in the case of Circuits, it contributes to determine the desired temperature of the circuit and so on.

The Working Mode may take on 3 different values, which are OFF, ECONOMY and COMFORT.
It is the Timetables, in most situations, to determine the current working mode of the various subsystems.

In the REG System, each Timetable allows to define up to 6 changes of Working Mode for each day of the week (Monday, Tuesday, …).

For each of these 6 changes is it possible to specify the corresponding time and mode.

In the REG System are available up to 8 Timetables, that is up to 8 different weekly programs can be determined for the various parts of the system (see TIMETABLES).

For example, we could use

A timetable for the operating times of the ground floor zones.
Another timetable for the operating times of the first floor zones.
Another timetable for the CMV operating times.
Another timetables for the times of the Domestic Hot Water production
… and so on... up to a maximum of 8 timetables.

It is possible to use the same timetable for several subsystems: if, for example, you wish that several Zones of the system are activated at the same time, it is possible to associate them all to the same clock; this simplifies the management of the system for the final user, who will have to program the operating times once for the entire system.

Zones

The main function of Zone type subsystem is to determine when the system should activate to heat/cool a part of the system (see INTRODUCTION TO ZONES).

Zones can combine several factors (room temperature, an external enable signal, current Working Mode, determined by the Timetable associated with the zone, and others) to determine whether a particular part of the system requires to be heated, cooled or dehumidified at a given time.

DHW (Domestic Hot Water)

The DHW subsystem is responsible to manage the production of Domestic Hot Water (see DHW ENABLE).

It can be considered as a Zone with special features and functions, specifically created to control hot water production; as the other Zones in the system, it is “powered” by a Timetable, that determines the current Working Mode, that “powers” in turn a Circuit.

In the System there is only one DHW subsystem; however, it is possible to make each of the 32 Zones of the system behave with the same peculiarities of the DHW subsystem, so in fact it is possible to have up to 33 DHW-type subsystems in the system!

Dehumidifiers

Dehumidifiers type subsystems deal with air dehumidification, with CMV system, and mainly with air-based heating/cooling integration system, such as fancoil.

Note

In fact, the name Dehumidifier assigned to this subsystem, is very limiting and it is a inheritance of the early versions of the REG System, when it “only” handled dehumidifiers; with the evolution of the REG System this subsystem has acquired many new functions and can be used to perform various tasks, but for simplicity and consistency it continues to be called “only” Dehumidifier.

Most of the Dehumidifier functions are carried out in conjunction with the Zones (which, as explained before, are responsible for determining the system’s requirements), but some basic functions for CMV management can also be managed independently by a Dehumidifiers, so there is a direct connection with the Timetables.

Circuits

The main function of Circuit-type subsystem is to manage the supply of energy to the system.

Circuits deal with various aspects that connect the Zones (that determine the system’s requirement) with the Sources (which produce the energy to satisfy this requirement), including:

The control of water pumps;
The determination of the temperatures set point (SET POINT AND SENSORS SETTINGS)
The control of the mixing valves (WATER PUMPS AND MIXING VALVES SETTINGS)

It is important to emphasize that the Circuits are not activated independently, but they are always activated by an upstream subsystem; specifically, circuits can be activated by a Zone, by a Dehumidifiers, or by DHW.

It is also possible to manage complex situation with distributions on several levels, where a circuit in turn actives other circuits (see FATHER CIRCUIT AND INTERLOCKED CIRCUIT).

Sources

Source-type subsystems manage the last link in the control chain, that is the production of the energy needed to heat, cool, and/or dehumidify the system.

In the Source subsystem, the logics for the management of Multiple Source, even of different types (so called hybrid system), are especially concentrated, and therefore all the parameters that contribute to determine which source is the best to use at a given time, taking into account all the system condition (Outdoor Temperature, fault conditions, priority, etc.).

It is important to emphasize that the Sources are not activated independently, but they are always activated by an upstream Circuit.

Cascade (Opentherm or ModBUS)

Cascade subsystem is a specific type of source (additional to the 3 “simple” Source of the previous paragraph) specialized in the management of systems composed of multiple generators (from 1 to 8) of the same type connected in such a way as to function as a single source.