ISO/FDIS 16484-4

Building automation and control systems (BACS) — Part 4: Control applications

This document specifies control applications and function blocks focusing on but not limited to lighting, solar protection, and HVAC applications. It describes how energy performance, comfort, and operational requirements of buildings are translated into functional specifications for integrated plant and room control.

Systèmes d'automatisation et de contrôle des bâtiments (BACS) — Partie 4: Applications de contrôle

General Information

• Status: Not Published
• ICS: 35.240.67 - IT applications in building and construction industry
• ICS: 91.040.01 - Buildings in general
• Technical Committee: ISO/TC 205 - Building environment design
• Drafting Committee: ISO/TC 205 - Building environment design
• Current Stage: 5000 - FDIS registered for formal approval
• Start Date: 10-Apr-2025
• Completion Date: 03-Jul-2024

Standards Content (Sample)

FINAL DRAFT
International
Standard
ISO/TC 205
Building automation and control
Secretariat: ANSI
systems (BACS) —
Voting begins on:
2025-05-23
Part 4:
Control applications
Voting terminates on:
2025-07-18
Systèmes d'automatisation et de contrôle des bâtiments
(BACS) —
Partie 4: Applications de contrôle
RECIPIENTS OF THIS DRAFT ARE INVITED TO SUBMIT,
WITH THEIR COMMENTS, NOTIFICATION OF ANY
RELEVANT PATENT RIGHTS OF WHICH THEY ARE AWARE
AND TO PROVIDE SUPPOR TING DOCUMENTATION.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO-
ISO/CEN PARALLEL PROCESSING LOGICAL, COMMERCIAL AND USER PURPOSES, DRAFT
INTERNATIONAL STANDARDS MAY ON OCCASION HAVE
TO BE CONSIDERED IN THE LIGHT OF THEIR POTENTIAL
TO BECOME STAN DARDS TO WHICH REFERENCE MAY BE
MADE IN NATIONAL REGULATIONS.
Reference number
FINAL DRAFT
International
Standard
ISO/TC 205
Building automation and control
Secretariat: ANSI
systems (BACS) —
Voting begins on:
Part 4:
Control applications
Voting terminates on:
Systèmes d'automatisation et de contrôle des bâtiments
(BACS) —
Partie 4: Applications de contrôle
RECIPIENTS OF THIS DRAFT ARE INVITED TO SUBMIT,
WITH THEIR COMMENTS, NOTIFICATION OF ANY
RELEVANT PATENT RIGHTS OF WHICH THEY ARE AWARE
AND TO PROVIDE SUPPOR TING DOCUMENTATION.
© ISO 2025
IN ADDITION TO THEIR EVALUATION AS
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO-
ISO/CEN PARALLEL PROCESSING
LOGICAL, COMMERCIAL AND USER PURPOSES, DRAFT
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
INTERNATIONAL STANDARDS MAY ON OCCASION HAVE
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
TO BE CONSIDERED IN THE LIGHT OF THEIR POTENTIAL
or ISO’s member body in the country of the requester.
TO BECOME STAN DARDS TO WHICH REFERENCE MAY BE
MADE IN NATIONAL REGULATIONS.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland Reference number
ii
Contents Page
Foreword .vi
Introduction .vii
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Abbreviated terms . 3
5 Functional specifications having an impact on energy performance, comfort, and
operational requirements of buildings . 3
5.1 Heating control .3
5.1.1 Emission control .3
5.1.2 Emission control for TABS (heating mode) .6
5.1.3 Control of distribution network hot water temperature (supply or return) .9
5.1.4 Control of distribution pumps in networks .10
5.1.5 Intermittent control of emission and/or distribution . 13
5.1.6 Heat generator control (combustion and district heating) .16
5.1.7 Heat generator control (heat pump) .18
5.1.8 Heat generator control (outdoor unit) .19
5.1.9 Sequencing of different heat generators . 20
5.1.10 Control of Thermal Energy Storage (TES) charging. 23
5.1.11 Hydronic balancing heating distribution (including contribution to balancing to
the emission side) .24
5.2 Domestic hot water (DHW) supply control . 26
5.2.1 Control of DHW storage charging with direct electric heating or integrated
electric heat pump . 26
5.2.2 Control of DHW storage charging using hot water generation .27
5.2.3 Control of DHW storage charging with solar collector and supplementary heat
generation . 29
5.2.4 Control of DHW circulation pump .31
5.3 Cooling control .32
5.3.1 Emission Control .32
5.3.2 Emission control for TABS (cooling mode) . 35
5.3.3 Control of distribution network chilled water temperature (supply or return) .37
5.3.4 Control of distribution pumps in hydraulic networks . 38
5.3.5 Intermittent Control of Emission and/or Distribution .41
5.3.6 Interlock between heating and cooling control of emission and/or distribution . 44
5.3.7 Generator control for cooling .45
5.3.8 Sequencing of different chillers (generators for chilled water) . 46
5.3.9 Control of Thermal Energy Storage (TES) charging. 48
5.3.10 Hydronic balancing cooling distribution (including contribution to balancing to
the emission side) . 49
5.4 Ventilation and air conditioning control .51
5.4.1 Supply air flow control at the room level.51
5.4.2 Room air temperature control by the ventilation system (all-air systems;
combination with static systems as cooling ceiling, radiators etc.) . 53
5.4.3 Coordination of room air temperature control by ventilation and by static
systems . 55
5.4.4 Outside air flow control . 56
5.4.5 Air flow or pressure control at the air handler level . .57
5.4.6 Heat recovery control (icing protection) . 60
5.4.7 Heat recovery control (prevention of overheating) .61
5.4.8 Free mechanical cooling .62
5.4.9 Supply air temperature control at the air handling unit level . 64
5.4.10 Humidity control . 65

iii
5.5 Lighting control . 66
5.5.1 Occupancy control . 66
5.5.2 Light level/Daylight control (daylight harvesting). 69
5.6 Blind control .71
5.6.1 Type 1 — Motorized operation of blind with manual control .71
5.6.2 Type 2 — Motorized operation of blind with automatic control . 72
5.6.3 Type 3 — Combined light/blind/HVAC control . 73
6 Functional elements . 74
6.1 Sensor functions.74
6.1.1 Air quality measurement .74
6.1.2 Air temperature measurement. 75
6.1.3 Dewpoint monitoring .76
6.1.4 Humidity measurement . 77
6.1.5 Brightness measurement . 78
6.1.6 Precipitation detection . 78
6.1.7 Presence detection . 79
6.1.8 Window monitoring . 80
6.1.9 Wind speed measurement . 81
6.1.10 Real-time clock . 82
6.1.11 Air volume flow measurement. 82
6.1.12 Partition wall position sensor .
...

ISO/DISFDIS 16484-4:2024(E)
ISO/TC 205
Secretariat: ANSI
Date: 2024-032025-05-08
Building automation and control systems — (BACS) —
Part 4:
Control applications
Systèmes d'automatisation et de contrôle des bâtiments (BACS) —
Partie 4: Applications de contrôle
FDIS stage
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication
may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying,
or posting on the internet or an intranet, without prior written permission. Permission can be requested from either ISO
at the address below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH--1214 Vernier, Geneva
Phone: + 41 22 749 01 11
EmailE-mail: [e-mail]
Website: www.iso.org
Published in Switzerland
ii
Contents
Foreword . iv
Introduction . v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Abbreviated terms . 3
5 Functional specifications having an impact on energy performance, comfort, and
operational requirements of buildings. 3
6 Functional elements . 87
Bibliography . 185

iii
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out through
ISO technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the
International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are described
in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types of
ISO documents should be noted. This document was drafted in accordance with the editorial rules of the
ISO/IEC Directives, Part 2 (see www.iso.org/directives).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent rights
in respect thereof. As of the date of publication of this document, ISO had not received notice of (a) patent(s)
which may be required to implement this document. However, implementers are cautioned that this may not
represent the latest information, which may be obtained from the patent database available at
www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions
related to conformity assessment, as well as information about ISO's adherence to the World Trade
Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 205, Building environment design, in
collaboration with the European Committee for Standardization (CEN) Technical Committee CEN/TC 247,
Building Automation, Controls and Building Management, in accordance with the Agreement on technical
cooperation between ISO and CEN (Vienna Agreement).
A list of all parts in the ISO 16484 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
iv
Introduction
Buildings are built and operated servingto serve a specific purpose, e.g. as an office workspace, a
manufacturing floor, or a data centre. In each case, the usage of the space requires specific environmental
conditions, e.g. temperature, light level or air quality.
Increasing the efficient usage of energy to provide these environmental conditions is a key aspect of building
design as addressed in ISO 52120--1.
Energy efficiency requirements cannot be fulfilled by optimizing the primary systems of a building alone. A
holistic view on the building and especially on the room control systems for lighting, solar protection and
heating, ventilation and air conditioning (HVAC) is the basis for optimizing the energy efficiency of buildings.
This requires integration of the room and building controls and management systems from the design phase
through installation and commissioning to the building operation.
The planning process for the technical infrastructure of a building and its spaces includes several steps
starting with a rough set of requirements. With each step in the planning process the design becomes more
detailed. Firstly, basic design choices or decisions allow for a budget estimate. These first design choices
maycan be documented as depicted in Figure 1Figure 1.
v
vi
NOTE Source:
SOURCE SN 502411:2016 / SIA 411:2016
Figure 1 — Example for documentation of design choices for technical infrastructure of a building
Figure 1Figure 1 shows equipment used for the different technical building disciplines (e.g. heating, cooling,
ventilation, lighting, solar protection) in the space including energy related interconnections between the
equipment of the respective disciplines. The schema depicts source/sink, conversion, storage, distribution,
and emission elements and their interconnections in a simple manner. This is a high-level view on the
mechanical and electrical equipment. It does not yet include the automation requirements associated with the
equipment.
In a further planning step, the control functions (BAC functions) associated with the technical infrastructure
equipment of a building are added as depicted in Figure 2Figure 2.
vii
viii
NOTE Source:
SOURCE SN 502411:2016 / SIA 411:2016
Figure 2 — Example for documentation of design choices for technical infrastructure and associated
control functions of a building
ix
The column “usage/operation” contains control functions used either for user interaction with the technical
building infrastructure in the space or for super-ordinated (e.g. building-wide) functions and requirements or
both.
Whereas the control functions are determined by the technical building equipment and the user operation
interface in general, the sophistication of these control functions is determined by the desired level of energy
efficiency of a building or comfort and operational requirements. Hence, in both views, the desired level of
energy efficiency of a building and the comfort and operational requirements, are considered and documented
such that this documentation serves as a requirement specification for building control applications (e.g.
heating, cooling, ventilation, lighting, solar protection) in a space.
In Figure 2Figure 2,, BAC functions have been added to the equipment. The labels refer to BAC functions listed
in ISO 52120--1:20222021, Table 5. These BAC functions are not specified in detail in ISO 52120--1.
Clause 5Clause 5 of this document provides a method to transfer energy performance, comfort, and
operational requirements as defined in ISO 52120--1:20222021 into a more detailed specification of building
automation functions.
ISO 52120--1:20222021, Table 5, contains a list of functions contributing to achieve the desired level of energy
performance. Whereas ISO 52120--1:2022 only provides a very brief description of the functionality,
Clause 5Clause 5 contains a more detailed description.
NOTE Application of automated control improves the energy performance of buildings. Clause 5Clause 5 of this
document covers automated control applications only. Any manual or non-automated control listed in ISO 52120--
1:20222021, Table 5, is not covered in this document.
For the purpose of clarity, each subclause in Clause 5Clause 5 identifies the corresponding entry in
EN ISO 52120--1:20222021, Table 5 directly after the sub-clause heading.
The more detailed description includes information about mandatory and optional inputs as well as
mandatory and optional outputs for the control function. The control function is not described in detail but
rather is a “black box” as the actual implementation can be project or manufacturer specific.
Figure 3Figure 3 provides an informative schematic view with the function (box), mandatory (blue) and
optional (grey) inputs and mandatory (blue) and optional (grey) outputs. The informative schematic drawing
also shows if inputs can be controlled, e.g. by manual operation or by a schedule, and if output values are
associated, e.g. with an alarm or a trend.
x
Figure 3 — Informative depiction of control application scheme for heating control –— Emission
control –— Type 1: Central automatic control
Clause 5Clause 5 contains in each sub-clause a brief description of the control function itself, the target of the
function, different operating modes, where applicable, and a description of the inputs and outputs of the
function. Optionally, parameters and implementation equipment may be described.
For some of these functions, more than one version is described, covering different technological
implementations.
Building control functions may be associated with a specific zone, a room, a building segment, or the whole
building.
The result of applying Clause 5Clause 5 is a collection of building automation control function blocks. This
does not yet depict how these blocks work in detail or how they are linked to each other. A more detailed
control scheme description can be provided using the function blocks described in Clause 6Clause 6.
Clause 6Clause 6 of this document provides function blocks, which can be used to describe building control
functions in more detail independent of a specific building control system or vendor.
Applications can be described by a combination of sensor input, actuator output, user interaction, and control
and monitoring functions. Certain functions in a room (e.g. presence detection) maycan be shared by two or
more applications. A common set of function blocks covering sensor input, actuator output, user interaction,
and control functions for the different applications in a room serves as the basis for describing room
automation, controls and management systems.
NOTE Room automation is coordinated control of lighting, solar protection, heating/ventilation/air conditioning
devices and systems in a room providing the desired comfort level with maximum energy efficiency. Using a typical
example, Figure 4Figure 4 shows the relationship between sensor, display/operation, control and actuator functions.
Information exchanged between functions is provided from outputs to inputs. Physical inputs and outputs associated
with sensor and actuator functions are not depicted in the Figure 3Figure 3. As some functions can require parameters,
these are also depicted in each function block.
xi
Figure 4 — Relationship between automation functions (typical example)
A sensor function typically includes a physical input (e.g. a temperature sensor, not depicted in
Figure 4Figure 4)) and provides a logical output (OUTPUT of the Sensor function block in Figure 4Figure 4))
for use by other functions.
A display and operation function includes physical inputs or outputs depending on its functionality and
provides logical inputs for display purposes and logical outputs for use by other functions (Display and
Operation function block in Figure 4Figure 4).).
Control functionality as depicted in Figure 4Figure 4 is assigned to specific control functions with one or more
logical inputs (INPUT 1 and INPUT 2 of the Control function block in Figure 4Figure 4)) and at least one logical
output (OUTPUT of the Control function block in Figure 4Figure 4).). Control functions are not directly
associated with physical inputs or outputs.
Actuator functionality is assigned to specific actuator functions. An actuator function typically includ
...