User Manual

Overview
General
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3.1 General
The first and most costly mistakes are already made during the planning phase. It is not uncommon to
submit faulty bids or bids that are not understandable. Planning offices generally fail to provide clear
answers to detailed queries since the requisite knowledge on networks is often lacking. Pay close attention
to the section on network and communications if a tender is involved.
It is fairly common to forget during initial clarifications to set up the system on an existing network or
infrastructure (rack, cabinets, switches, cabling, etc.) at the customer. An appropriate examination can
save unnecessary costs.
Provided of course that the customer's infrastructure meets the same requirements for reliability,
performance, availability, expandability, IT security, etc. as described in this document. If new networks are
unavoidable, it makes sense to consider topics such as digitalization, cloud solutions, scalability, and
flexible administration using virtual and easy-to-administer networks.
Building automation and control systems do not play a significant role here.
3.1.1 Functions in a building automation and control system
The goal of a building automation and control system (BAC system) is to achieve and maintain an optimum
level of comfort and the lowest possible energy. The classical building automation and control system is
divided into three levels (even when using a standardized communication protocol BACnet):
● Management level
● Automation level
● Field level
In a Desigo system, this can be described in greater detail through functions and applications.
Plant scope
Here is where the automation stations are located that take over control of primary plants such as air
handling units, heating circuits, and cooling circuits to supply the rooms or heating or refrigeration plants.
The plants are always demand-controlled over the supply chain, in other words, heat or cooling demand
occurs in a room that is forwarded to the applicable generation or over the heating or cooling circuit.
Floor scope
This is where rooms and room segments are controlled - energy-efficient HVAC functions, but also lighting
and shading systems ensure optimum room conditions.
In an HVAC environment, we have radiators, and/or heating/chilled ceilings, but also fan coil units as well
as variable air flow systems. On primary plants, hot or chilled water, but also treated air, is provided based
on demand and is treated in the room segment by radiators, heated/chilled ceilings, heating or cooling
coils. Blinds control can be used in addition to daylight or indirect lighting to heat and cool the room.
Lighting control is also integrated to provide optimum lighting, together as well with blinds control.
Central functions specify, from the superposed location (Building Scope), for example, the room operating
mode as well as room setpoints for the room or a group of rooms. The room user can also intervene with
local room operator units and adapt room conditions to his or her needs.
Building Scope
Superposed central functions, e.g. a weather station, can generate setpoints for assigned rooms based on
the outside air temperature. A scheduler can form and distribute a room operating mode for assigned
rooms in a building section or floor. Moreover, lighting and blinds components can be deployed to a defined
state via protection, service, or emergency functions. Demand signals from the rooms (Floor scope) are
evaluated here and compiled and forwarded to the primary plants such as central air handling, heating or
cooling circuits (located in the Plant Scope).
The following image illustrates the devices and functions located in different scopes and how the
communication paths are defined. It illustrates that the floor scope does not require interaction to another
floor scope nor permits and supports interaction; conversely, functions and applications communicate in
the building scope with floor and plant scopes. The plant scope processes the information (forced and
demand signals) from the building scope.