ISO/IEC 10192-3:2017

ISO/IEC 10192-3
Edition 1.0 2017-11
INTERNATIONAL
STANDARD
colour
inside
Information technology – Home electronic system (HES) interfaces –
Part 3: Modular communications interface for energy management

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ISO/IEC 10192-3
Edition 1.0 2017-11
INTERNATIONAL
STANDARD
colour
inside
Information technology – Home electronic system (HES) interfaces –

Part 3: Modular communications interface for energy management

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 35.200 ISBN 978-2-8322-5099-0

– 2 – ISO/IEC 10192-3:2017 © ISO/IEC 2017
CONTENTS
FOREWORD . 7
INTRODUCTION . 8
1 Scope . 10
2 Normative references . 10
3 Terms, definitions and abbreviated terms . 11
3.1 Terms and definitions . 11
3.2 Abbreviated terms . 11
4 Conformance . 12
5 Physical/electrical Interface . 12
5.1 Form factors . 12
5.2 Removal and exchange of a UCM . 12
5.3 Block diagram . 12
6 Serial protocol . 13
6.1 Protocol data unit . 13
6.2 Message Type field . 13
6.3 Payload length field . 14
6.4 Checksum field . 15
6.5 Bit and byte order . 15
6.5.1 Bit order within a byte . 15
6.5.2 Byte order for multi-byte messages . 15
6.6 Message synchronization and timing . 15
6.6.1 Message sequencing . 15
6.6.2 Link layer timing . 15
6.6.3 Randomized link layer retries . 17
6.6.4 Application layer timing . 17
6.7 SGD handling of conflicting messages . 18
7 Simple Protocol . 18
8 Link layer . 19
8.1 Use of link layer messages . 19
8.2 Link layer ACK/NAK . 19
8.3 Message Type “supported query” . 20
9 Data-link messages . 21
9.1 Message format . 21
9.2 Interface power limit negotiation . 23
9.3 Bit rate negotiation . 24
9.4 Power-up and state reset . 25
9.5 Security . 25
9.6 Setting slot numbering . 25
10 Basic DR application (Message Type = 0x08, 0x01) . 26
10.1 Basic DR application commands . 26
10.1.1 Message format . 26
10.1.2 Basic message fixed length . 30
10.1.3 Event Duration field . 30
10.1.4 Grouped messages . 31
10.2 Usage and details of basic DR application messages . 31
10.2.1 Request for power level (Opcode 0x06) . 31

10.2.2 Relative price commands (Opcode 0x07 and 0x08) . 32
10.2.3 Time remaining in present price period (Opcode 0x09) . 33
10.2.4 Operating state monitoring (Opcodes 0x12 and 0x13) . 33
11 Intermediate DR application (Message Type = 0x08, 0x02) . 35
11.1 Intermediate DR message set . 35
11.2 Usage and details of Intermediate DR application messages . 38
11.2.1 Info request . 38
11.2.2 Get/Set UTC time . 41
11.2.3 Get/Set energy price . 42
11.2.4 Get/Set tier . 44
11.2.5 Get/Set temperature offset. 45
11.2.6 Get/Set set point . 46
11.2.7 Autonomous cycling . 47
11.2.8 Demand reduction – terminate cycling . 49
11.3 Demand response event schedules . 49
11.3.1 Function . 49
11.3.2 Send scheduled events request . 50
11.4 Energy consumption . 50
11.4.1 Function . 50
11.4.2 Commodity read . 50
11.4.3 Get/Set CommodityType . 53
12 Commissioning and network messages (Message Type = 0x08, 0x04) . 55
13 Pass-Through Mode . 55
13.1 Pass-Through method . 55
13.1.1 General . 55
13.1.2 Full Encapsulation in the Message Payload . 56
13.1.3 Message Type Field . 56
13.1.4 Message Type Support Query . 56
13.1.5 Maximum Message Length Negotiation . 56
13.1.6 Pass-Through mode protocols . 56
13.2 Pass-Through mode protocols. 56
13.2.1 USNAP 1.0 protocol Pass-Through . 56
13.2.2 SEP1.0 or 1.1 Pass-Through . 57
13.2.3 ClimateTalk Pass-Through . 57
13.2.4 General Internet Protocol Pass-Through . 57
13.2.5 ISO/IEC 14543-4-3 Pass-Through . 58
13.2.6 ISO/IEC 14543-3-1 Pass-Through . 58
13.2.7 ISO/IEC 14908-1 Pass-Through . 59
13.2.8 SunSpec Pass-Through . 59
14 Typical communication exchanges . 59
15 General security principles . 60
16 Load management event randomization . 60
Annex A (normative) Low voltage DC form factor . 62
A.1 General . 62
A.2 Limitations . 62
A.3 Power for UCM . 62
A.4 Mechanical interface . 62
A.4.1 DC form factor board layout . 62

– 4 – ISO/IEC 10192-3:2017 © ISO/IEC 2017
A.4.2 Module configuration . 63
A.4.3 Form factor . 66
A.4.4 Housing materials . 66
A.4.5 Connector type . 66
A.4.6 Pin assignments . 67
A.5 Electrical interface . 67
A.5.1 Electrical Interface Levels . 67
A.5.2 Signal timing . 67
A.5.3 Interface circuits . 68
A.6 Data transfer protocol . 68
A.6.1 Control signals. 68
A.6.2 Clock and data rate . 69
A.6.3 Multiple slots . 69
A.7 Link layer data flow . 69
A.8 Messages . 69
A.8.1 Frame structure . 69
A.8.2 Message synchronization (frame delimiting) . 69
A.8.3 Message filling (inter-message byte filling) . 69
A.8.4 Command/Response encoding . 70
A.8.5 Checksum calculation . 70
A.8.6 Master/Slave . 70
A.8.7 Flow control . 70
A.8.8 Error detection and recovery . 70
A.9 Operation . 71
A.9.1 Transaction sequence. 71
A.9.2 SPI data transfer state machine . 74
A.9.3 SGD transmitter operation . 75
A.9.4 SGD device receiver operation . 75
A.9.5 UCM operations . 76
Annex B (informative) Description of DC form factor applications . 77
B.1 General . 77
B.2 Applications of ISO/IEC 24379 . 77
B.3 Physical Form Factor Review . 77
B.4 Observations with regard to UCM and ATA confusion . 78
B.4.1 General . 78
B.4.2 ATA into Smart Grid Device . 78
B.4.3 Universal Communication Module into ATA device bay . 78
B.5 Conclusion . 78
Annex C (normative) AC form factor. 79
C.1 General . 79
C.2 Physical form . 79
C.2.1 AC SGD and AC UCM connector . 79
C.2.2 AC enclosure requirements . 84
C.3 AC power . 87
C.4 Obtaining message sync . 89
Annex D (normative) Fletcher checksum . 90
D.1 Checksum method . 90
D.2 Calculating the checksum . 90
D.3 Decoding the checksum . 90

Annex E (informative) Example Visual Basic code . 91
Annex F (informative) Guideline for computing average price. 92
F.1 Average Price versus Time Varying Charges . 92
F.2 Relative price command . 92
F.3 Explanation for non-regulated utilities . 93
F.4 Summary . 93
Annex G (informative) Product safety considerations . 95
Bibliography . 96

Figure 1 – Illustrations of the modular communications interface (MCI) concept . 9
Figure 2 – Modular communications interface (MCI) block diagram . 13
Figure 3 – Link layer timing . 16
Figure 4 – Application layer timing . 17
Figure 5 – Non-linear event duration scaling . 31
Figure 6 – Non-linear relative price scaling . 33
Figure 7 – Illustration of energy storage capacity . 53
Figure 8 – Internet Protocol Pass-Through (IPv6) . 58
Figure 9 – Illustration of randomization of events by communications modules . 61
Figure A.1 – DC form factor PCB dimensions . 63
Figure A.2 – DC form factor housing dimensions – top view . 64
Figure A.3 – DC form factor housing dimensions – side view . 65
Figure A.4 – DC form factor housing dimensions – end view . 66
Figure A.5 – Pin assignment . 67
Figure A.6 – SPI Mode 0 bit timing . 67
Figure A.7 – SPI transaction sequence: SGD-initiated message to the UCM . 71
Figure A.8 – SPI transaction sequence: UCM-initiated message to the SGD . 72
Figure A.9 – SPI data transfer state machine . 74
Figure C.1 – Panel-mount AC connector form factor (device side shown) and pin-out . 80
Figure C.2 – PCB-mount AC UCM connector (housing) . 80
Figure C.3 – Cable AC UCM connector (housing) . 81
Figure C.4 – Panel mount AC SGD connector form factor dimensions . 82
Figure C.5 – PCB mount connector dimensions . 83
Figure C.6 – Cable connector dimensions . 83
Figure C.7 – Contact dimensions for cable connector and PCB mount connector . 84
Figure C.8 – Reserved area and dimensions on SGD (receptacle) . 85
Figure C.9 – Right side and top view of maximum UCM dimensions . 86
Figure C.10 – Left side and bottom view of maximum UCM dimensions . 87
Figure C.11 – Typical RS-485 polarity and byte transfer . 88
Figure C.12 – RS-485 connections . 88

Table 1 – Protocol data unit format . 13
Table 2 – Message type assignments . 14
Table 3 – Message timing requirements . 16
Table 4 – Basic/Intermediate DR application layer timing parameters . 18

– 6 – ISO/IEC 10192-3:2017 © ISO/IEC 2017
Table 5 – Mandatory message summary . 19
Table 6 – ACK/NAK Packet . 19
Table 7 – Link layer NAK codes . 20
Table 8 – Message type “supported query” . 20
Table 9 – Data-link message format . 21
Table 10 – Data-link command set . 22
Table 11 – Interface power level indicator codes . 23
Table 12 – Bit rate indicator . 25
Table 13 – Basic application data format . 26
Table 14 – Basic DR application command set . 27
Table 15 – Operating state codes . 34
Table 16 – Operating-state codes for usage conditions . 35
Table 17 – Intermediate DR application command set (command byte description) . 36
Table 18 – Intermediate DR application command set . 37
Table 19 – Response code values . 38
Table 20 – Commissioning and network messages . 55
Table 21 – Pass-Through message . 56
Table 22 – USNAP1.0 over serial . 56
Table 23 – SEP1.0 or 1.1 over serial. 57
Table 24 – ClimateTalk over serial . 57
Table 25 – ISO/IEC 14543-4-3 over serial . 58
Table 26 – ISO/IEC 14543-3-1 over serial . 59
Table 27 – ISO/IEC 14908-1 over serial . 59
Table 28 – SunSpec over serial . 59
Table A.1 – Low voltage interface signal definitions . 68
Table A.2 – SPI physical timing requirements . 73

INFORMATION TECHNOLOGY –
HOME ELECTRONIC SYSTEM (HES) INTERFACES –

Part 3: Modular communications interface for energy management

FOREWORD
1) ISO (the International Organization for Standardization) and IEC (the International Electrotechnical Commission)
form the specialized system for worldwide standardization. National bodies that are members of ISO or IEC
participate in the development of International Standards through technical committees established by the
respective organization to deal with particular fields of technical activity. ISO and IEC technical committees
collaborate in fields of mutual interest. Other international organizations, governmental and non-governmental, in
liaison with ISO and IEC, also take part in the work. In the field of information technology, ISO and IEC have
established a joint technical committee, ISO/IEC JTC 1.
2) The formal decisions or agreements of IEC and ISO on technical matters express, as nearly as possible, an
international consensus of opinion on the relevant subjects since each technical committee has representation
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responsible for the way in which they are used or for any misinterpretation by any end user.
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apply IEC, ISO and ISO/IEC publications transparently to the maximum extent possible in their national and
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6) All users should ensure that they have the latest edition of this publication.
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8) Attention is drawn to the normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this ISO/IEC publication may be the subject of
patent rights. ISO and IEC shall not be held responsible for identifying any or all such patent rights.
International Standard ISO/IEC 10192-3 was prepared by subcommittee 25: Interconnection
of information technology equipment, of ISO/IEC joint technical committee 1: Information
technology.
This International Standard has been approved by vote of the member bodies, and the voting
results may be obtained from the address given on the second title page.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts in the ISO/IEC 10192 series, published under the general title Information
technology – Home electronic system (HES) interfaces, can be found on the IEC and ISO
websites.
IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates
that it contains colours, which are considered to be useful for the correct
understanding of its contents. Users should therefore print this document using a
colour printer.
– 8 – ISO/IEC 10192-3:2017 © ISO/IEC 2017
INTRODUCTION
Utilities world-wide are investing heavily in smart grid infrastructures for energy that extend to
homes and businesses with the goal of improving grid reliability and efficiency through
increased consumer awareness and participation. This document provides a solution for grid
connections within the home through a modular communications interface (MCI) enabling any
product to connect to a variety of demand-response systems. Such systems may include
Advanced Metering Infrastructure (AMI), Smart Energy Profile (SEP),
IEC PAS 62746-10-1:2014 (OpenADR 2.0) and/or home or building networks such as
protocols specified in the ISO/IEC 14543 series. The concept is simple: encourage
manufacturers to build an MCI into their products that can accept a simple communications
module. Consumers and programme managers are then free to select whatever
communications solution works best for their particular environment.
The MCI is based on the ISO/IEC 8482 interface (commonly referenced as RS-485) and the
Serial Peripheral Interface (SPI) supported by most silicon chips. The messages conveyed
through the MCI to the end-device use either an externally specified command set (called the
“Pass-Through mode”) or the demand response (DR) application command set specified in
this document as the Simple Protocol. The DR command set is intended for devices that
cannot process one of the “pass-through” command sets. This document specifies options for
the Pass-Through mode based on protocols commonly used in grid applications such as
Internet Protocol (IP), IEC PAS 62746-10-1:2014 (OpenADR 2.0), SEP, and ISO/IEC 14543
series protocols. Network security is supported at the application layer in the Pass-Through
mode in addition to network or application layer security.
The MCI specified in this document may use either of the following connectors:
• an AC powered form, which uses the ISO/IEC 8482 interface over a physical connector
defined in this document;
• a DC powered form, which uses the Serial Peripheral Interface over a connector defined in
ISO/IEC 24739-3. The use of this connector is discussed in Annex A and Annex B.
The MCI applies to devices that may include an energy management hub, an energy
management controller, an energy management agent, a residential gateway, an energy
services interface, a sensor, a thermostat, an appliance or other consumer products. A
physical connection from a communication module to residential smart grid devices and
options for a communications protocol including application messages are specified. The
specific residential devices to use an MCI are not specified. For energy management the
choice depends on the system and the network topology. If a hub topology is chosen, the MCI
may be located on the hub. The connection between the hub and end-devices such as
appliances is not specified.
Communication messages specified in this document for the DR command set support direct
load control, time-of-use (TOU), critical-peak-pricing (CPP), real-time pricing (RTP), peak time
rebates, various types of block rates, and a range of ancillary services. The functionality of
the removable MCI modules can be tailored by utilities or other load managing entities to
provide support for the unique needs in a given region or service territory without impacting
the end-devices. Figure 1 illustrates the general concept of the MCI.

IEC
IEC
a) MCI on a controlled device b) MCI on an energy management console
Figure 1 – Illustrations of the modular communications interface (MCI) concept
This document enables a new generation of “smart grid ready” products that limit risks and
constraints of proprietary communication technologies and evolving standards. This approach
simplifies home area network (HAN) device and network interoperability, fosters programme
and product innovation and opens DR programmes to a broader range of consumer products,
while facilitating customer choice and a competitive market landscape.

– 10 – ISO/IEC 10192-3:2017 © ISO/IEC 2017
INFORMATION TECHNOLOGY –
HOME ELECTRONIC SYSTEM (HES) INTERFACES –

Part 3: Modular communications interface for energy management

1 Scope
This part of IEC 10192 specifies a UCM (Universal Communications Module) that transfers
energy management data via a home network between an end-device and an energy
management agent (specified in ISO/IEC 15067-3) or an energy service provider. This
document specifies the mechanical, electrical and logical characteristics of the interfaces of
UCM to an end-device (hereafter referred to as an SGD – Smart Grid Device) and a choice of
interfaces to a home communications network.
This document specifies the physical and data-link characteristics of the interface between
the UCM and the SGD, along with certain higher-layer and application layer elements as
needed to assure interoperability over a broad range of device capabilities. It specifies a
mechanism through which network, transport and application layer messages specified in
other documents listed in this document may be passed through the interface. For those end-
devices that cannot process one of the “pass-through” command sets, a Simple Protocol is
specified according to the OSI (Open System Interconnect) reference model (ISO/IEC 7498-1)
including application layer messaging for energy management.
The UCM specified in this document is intended to be installable by the purchaser, home
occupant or professional installer. The connectors are integrated in a way that allows for
easy, plug-in installation. However, the manufacturer may choose to pre-install a module
during production or have installation handled by a manufacturer representative or
professional installer.
The scope of this document does not include safety related construction, performance,
marking or instruction requirements. UCM products should additionally comply with applicable
product safety standard(s). Examples of such standards are presented in Annex G.
NOTE Some regulatory authorities require that appliances intended for participation in energy management, such
as thermostats, be user installable.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their
content constitutes requirements of this document. For dated references, only the edition
cited applies. For undated references, the latest edition of the referenced document (including
any amendments) applies.
ISO/IEC 8482, Information technology – Telecommunications and information exchange
between systems – Twisted pair multipoint interconnections
ISO/IEC 14543-3-1, Information technology – Home electronic system (HES) architecture –
Part 3-1: Communication layers – Application layer for network based control of HES Class 1
ISO/IEC 14543-4-3, Information technology – Home electronic system (HES) architecture –
Part 4-3: Application layer interface to lower communications layers for network enhanced
control devices of HES Class 1
ISO/IEC 14908-1, Information technology – Control network protocol – Part 1: Protocol stack

ISO/IEC 24739-3, Information technology – AT attachment with packet interface-7 – Part 3:
Serial transport protocols and physical interconnect (ATA/ATAPI-7 V3)
ISO 4217, Codes for the representation of currencies
IEC PAS 62746-10-1:2014, Systems interface between customer energy management system
and the power management system – Part 10-1: Open Automated Demand Response
(OpenADR 2.0b Profile Specification)
3 Terms, definitions and abbreviated terms
3.1 Terms and definitions
3.1.1
average price
equivalent constant price for electricity as determined by the energy service provider
3.1.2
hot-swappable
connected and removed under load
3.1.3
Pass-Through mode
use of one of the following application layer protocols: Advanced Metering Infrastructure
(AMI), Smart Energy Profile (SEP), IEC PAS 62746-10-1:2014 (OpenADR 2.0) and/or home or
building networks specified in the ISO/IEC 14543 series
3.1.4
relative price
ratio of the current price to the average price, where “Average_Price” is calculated as
specified in Annex F
3.1.5
smart grid device
end-device that is being informed of energy grid conditions
3.1.6
universal communications module
communications device that provides communication connectivity to a smart grid device
3.2 Abbreviated terms
AMI Advanced Metering Infrastructure
AP Average Price
ATA Advanced Technology Attachment
CPP Critical Peak Price
DR Demand Response
HVAC Heating, Ventilation and Air Conditioning
IP Internet Protocol
LS Least Significant
MS Most Significant
OpenADR Automated Demand Response specification from the OpenADR Alliance
PCB Printed Circuit Board
PLC Power Line Carrier
– 12 – ISO/IEC 10192-3:2017 © ISO/IEC 2017
PoE Power over Ethernet
RBDS Radio Broadcast Data System
RDS Radio Data System
SEP Smart Energy Profile
SGD Smart Grid Device
SPI Serial Peripheral Interface (data transfer standard originally specified by
Motorola (Freescale))
TVC Time Varying Charges
UCM Universal Communications Module
UTC Universal Coordinated Time
0x00 to 0xFF Two digit (8 bit) hexadecimal numbers ranging from 0 to 255 decimal
b0, b1 . b15 Bit values within a hexadecimal number. b0 is the least significant bit.
4 Conformance
In order to conform to this document a UCM shall transfer energy management data between
an end-device and an energy management agent or an energy service provider via a home
network, provide an interface to the device (as specified in Clause 5 with a DC interface as
specified in Annex A or an AC interface as specified in Annex C) and provide an interface to a
home network as specified in Clause 6.
The messaging format shall be one of the protocols referenced in Clause 13 or the Simple
Protocol specified in Clauses 7, 8, 9, 10, 11 and 12.
5 Physical/electrical Interface
5.1 Form factors
Two physical form factors are specified. End-device manufacturers may choose either, and
communications module providers who wish to cover all products may offer two module
versions. For both form factors, the communications protocol across the socket interface is
the same, as described herein. Also in both cases, the power for the UCM is provided by the
SGD. One form factor provides a low voltage DC supply and an SPI serial data interface. This
form factor is specified in Annex A. This option might be attractive in cases where the end-
device has no AC power source or when smaller socket size is required.
The second form factor provides AC service voltage for a single phase (typically 120 V or
240 V depending on the country and the appliance) and an ISO/IEC 8482-based serial
interface. This form factor is specified in Annex C. This option might be attractive in cases
where the end-device does not provide a DC power supply, where compatibility with PLC
communications modules is desired or where communications module access to line
frequency is needed.
NOTE 1 ISO/IEC 8482 was originally developed as RS-485 and TIA-485.
5.2 Removal and exchange of a U
...