ISO/IEC 14543-4-304:2026

ISO/IEC 14543-4-304
Edition 1.0 2026-06
INTERNATIONAL
STANDARD
Information technology - Home Electronic System (HES) architecture -
Part 4-304: Application protocol for electric vehicle supply equipment (EVSE)
charger and dischargers and controllers
ICS 35.020  ISBN 978-2-8327-11345-7

ISO/IEC 14543-4-304: 2026-06(en)

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CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 6
3 Terms, definitions, and abbreviated terms . 6
3.1 Terms and definitions. 6
3.2 Abbreviated terms . 8
4 Conformance . 8
5 Configuration . 8
6 Application layer . 10
6.1 General . 10
6.2 NECD objects . 10
6.3 NECD services . 11
6.4 Object-specific NECD properties . 11
6.5 Application operation . 13
6.5.1 General . 13
6.5.2 Continuous requests . 13
6.5.3 Response wait time value for controllers . 13
6.5.4 Resending a frame . 14
6.5.5 Processing object property counter . 14
6.5.6 Property values of write requests . 14
6.5.7 Property values of read requests . 14
7 Normal operation . 15
7.1 General . 15
7.2 Start-up operation . 15
7.2.1 General . 15
7.2.2 Start-up processing of NECD nodes . 15
7.2.3 Search processing . 16
7.2.4 Obtaining NECD attribute information . 16
7.2.5 Obtaining EVSE charger and discharger attribute information . 17
7.3 Occasional operation . 18
7.3.1 General . 18
7.3.2 Obtaining vehicle connection and chargeable or dischargeable status . 18
7.3.3 Controlling EVSE charger and discharger when chargeable and not
dischargeable . 20
7.3.4 Controlling EVSE charger and discharger when dischargeable and not
chargeable . 23
7.3.5 Controlling EVSE charger and discharger when chargeable and
dischargeable . 25
7.4 Fault status notification . 28
8 Remote control . 28
9 Considerations on controllers . 29
Annex A (informative) Terms and NECD protocol frame format on ISO/IEC 14543-4-3
and IEC 62394 . 30
A.1 Terms correspondence between ISO/IEC 14543-4-3 and IEC 62394 . 30
A.2 NECD protocol frame format . 30
Annex B (informative) Communication link between EVSE charger and discharger and
CEM in IEC 63380-1 . 32
Annex C (informative) Relationship between ISO/IEC 14543-4 series and the HES
gateway, based on ISO/IEC 15045 series and ISO/IEC 18012 series . 33
Bibliography . 45

Figure 1 – Relationship between IEC 62394, ISO/IEC 14543-4-3, and
ISO/IEC 14543‑4‑304. 5
Figure 2 – Physical configuration, and the path and direction of electricity and

communication . 9
Figure 3 – Connection configurations . 9
Figure 4 – Assumed network stack. 10
Figure 5 – Summary of normal operation sequences . 15
Figure 6 – Sequence for obtaining NECD attribute information . 17
Figure 7 – Sequence of obtaining EVSE charger and discharger attribute information . 18
Figure 8 – Sequence to obtain vehicle connection and chargeable status of EVSE
charger and discharger . 20
Figure 9 – Sequence to control EVSE charger and discharger when chargeable and
not dischargeable . 22
Figure 10 – Sequence to control EVSE charger and discharger when dischargeable
and not chargeable . 24
Figure 11 – Sequence to control EVSE charger and discharger when chargeable and
dischargeable . 27
Figure 12 – Remote control . 28
Figure A.1 – NECD protocol frame format . 31
Figure B.1 – Communication link between EVSE charger and discharger and CEM in
IEC 63380-1 . 32
Figure C.1 – Measurement points for AC EVSEs translated into ISO/IEC 18012-3 . 44
Figure C.2 – Measurement points for DC EVSEs translated into ISO/IEC 18012-3 . 44

Table 1 – NECD objects for EVSE charger and dischargers . 10
Table 2 – NECD objects for controllers . 10
Table 3 – NECD services . 11
Table 4 – NECD properties of device object (super class) . 11
Table 5 – NECD properties of device object . 12
Table 6 – Response wait time values for controllers . 13
Table A.1 – Terms correspondence table between ISO/IEC 14543-4-3 and IEC 62394 . 30
Table C.1 – List of the translation between ISO/IEC 14543-4-304, IEC 62394, and
HES gateway lexicon (ISO/IEC 18012‑3) supported . 33
Table C.2 – List of the translation between ISO/IEC 14543-4-304, IEC 62394, and HES
gateway lexicon (ISO/IEC 18012‑3) not supported at this time . 42

Information technology -
Home Electronic System (HES) architecture -
Part 4-304: Application protocol for electric vehicle supply
equipment (EVSE) charger and dischargers and controllers

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
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2) The formal decisions or agreements of IEC and ISO on technical matters express, as nearly as possible, an
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3) IEC and ISO documents have the form of recommendations for international use and are accepted by IEC and
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8) Attention is drawn to the Normative references cited in this document. Use of the referenced publications is
indispensable for the correct application of this document.
9) IEC and ISO draw attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). IEC and ISO take no position concerning the evidence, validity or applicability of any claimed patent
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may not represent the latest information, which may be obtained from the patent database available at
https://patents.iec.ch and www.iso.org/patents. IEC and ISO shall not be held responsible for identifying any or
all such patent rights.
ISO/IEC 14543-4-304 has been prepared by subcommittee 25: Interconnection of information
technology equipment, of ISO/IEC joint technical committee 1: Information technology. It is an
International Standard.
The text of this International Standard is based on the following documents:
Draft Report on voting
JTC1-SC25/3322/CDV JTC1-SC25/3347/RVC

Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
The list of all currently available parts of the ISO/IEC 14543 series, under the general title
Information technology - Home Electronic System (HES) architecture, can be found on the IEC
website and ISO website.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1, available at
www.iec.ch/members_experts/refdocs and www.iso.org/directives.

INTRODUCTION
The ISO/IEC 14543 series provides networking capability for a wide range of appliances,
equipment, sensors, etc. in the home, including lighting, heating, and cooling. This part of
ISO/IEC 14543 specifies the detailed procedures and behaviours of both electric vehicle supply
equipment (EVSE) charger and dischargers and controllers at the application level of
communications based on ISO/IEC 14543-4-3. This document specifies the message structure,
sequences, and protocol of the application layer for networked enhanced control devices
(NECDs) used in the Home Electronic System (HES). Some services are targeted for
communications between devices. Other services are exclusively reserved for management
purposes. Some services can be used for both management and run-time communications. This
document is applicable for energy management services involving EVSE charger and
dischargers and related devices.
Figure 1 shows the relationship between IEC 62394, ISO/IEC 14543-4-3 and
ISO/IEC 14543-4-304. ISO/IEC 14543-4-3 specifies the message structure, sequences and
protocol for general-purpose communications used in network enhanced control devices of the
Home Electronic System (HES) Class 1. ISO/IEC 14543-4-3 provides the common interfaces
for the use-level process and the services such as energy management, remote maintenance,
and other services for easily building a system consisting of multi-vendor devices and
equipment. IEC 62394 specifies the detailed lists of control commands on NECD objects (see
ISO/IEC 14543-4-3). Annex A shows terms and NECD protocol frame format on
ISO/IEC 14543-4-3 and IEC 62394.

Application protocol:
ISO/IEC 14543-4-304
specified for each device
class
Application layer
Control commands IEC 62394
NECD Protocol ISO/IEC 14543-4-3
Transport layer
Network layer
MAC layer
PHY layer
Figure 1 – Relationship between IEC 62394, ISO/IEC 14543-4-3, and ISO/IEC 14543‑4‑304
ISO/IEC 14543-4-3 is a general-purpose communications specification that applies to a variety
of devices. ISO/IEC 14543-4-3 is the basis for this document, which specifies detailed
procedures and behaviours for pre-packaged system solutions that include EVSE charger and
dischargers and related devices. The procedures and behaviours specified in this document
can be used for energy flow inside a home or energy flow between the grid and a home.
In order to enhance interoperability, it is important to specify how to implement
ISO/IEC 14543-4-3 for each device and controller at the application level such as command
sequences, timeout requirements, required combinations of acceptable commands, minimum
subset of IEC 62394 properties, etc.
This document applies to the communication link in yellow between charging station (EVSE
charger and discharger) and energy management system (EMS) as shown in Annex B.

1 Scope
This part of ISO/IEC 14543 specifies an application-layer protocol important for ensuring
interoperability among the products of various manufacturers regarding communications
between electric vehicle supply equipment (EVSE) charger and dischargers and controllers. It
uses the network enhanced communications device (NECD) protocol specified in
ISO/IEC 14543-4-3. This protocol is based on UDP using IPv4 or IPv6 (TCP is optional).
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.
IEC 62394, Service diagnostic interface for consumer electronics products and networks -
Implementation for ECHONET
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
3 Terms, definitions, and abbreviated terms
3.1 Terms and definitions
For the purposes of this document the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following
addresses:
– IEC Electropedia: available at https://www.electropedia.org/
– ISO Online browsing platform: available at https://www.iso.org/obp
3.1.1
controller
network enhanced control device (NECD) node that sends NECD requests (Get and SetC) to
another NECD node
Note 1 to entry: A controller in this document can be used as a part of a customer energy manager (CEM) specified
in IEC 63380-1.
Note 2 to entry: A controller in this document can be used with an energy management agent (EMA) specified in
ISO/IEC 15067-3.
Note 3 to entry: A controller in this document can be used with a resource manager (RM) specified in IEC 63402-1.
3.1.2
device object
network enhanced control device (NECD) object other than a node profile object
Note 1 to entry: In this document, "device object" refers to electric vehicle charger/discharger object only.
[SOURCE: ISO/IEC 14543-4-302:2023, 3.1.3, modified – In Note 1 to entry, "storage battery"
has been replaced with "electric vehicle charger/discharger".]
3.1.3
electric vehicle
EV
vehicle that is powered by an electric motor that draws electricity from a battery and is capable
of being charged from an external source
Note 1 to entry: In this document, "electric vehicle" refers to both a vehicle that is only powered by an electric motor
that draws electricity from a battery and a vehicle that is powered by an electric motor that draws electricity from a
battery and by an internal combustion engine.
Note 2 to entry: In this document, "electric vehicle" refers to both a vehicle that contains a device that converts
alternating current (AC) voltage to direct current (DC) voltage or DC voltage to AC voltage (e.g. inverter) and a
vehicle that does not contain a device that converts AC voltage to DC voltage or DC voltage to AC voltage.
3.1.4
electric vehicle supply equipment
EVSE
device that transfers electricity between electric vehicle and home or grid
Note 1 to entry: In this document, "electric vehicle supply equipment" refers to both a device that contains a device
that converts alternating current (AC) voltage to direct current (DC) voltage or DC voltage to AC voltage (e.g. inverter)
and a device that does not contain a device that converts AC voltage to DC voltage or DC voltage to AC voltage.
Note 2 to entry: In this document, "electric vehicle supply equipment" refers to a device that supports primarily
single-family residential applications.
3.1.5
electric vehicle supply equipment charger and discharger
EVSE charger and discharger
electric vehicle supply equipment that includes a communications interface of NECD protocol
and is capable of transferring electricity both from home or grid to electric vehicle (EV) and from
EV to home or grid
3.1.6
NECD protocol
protocol used in network enhanced control device (NECD) communications
[SOURCE: ISO/IEC 14543-4-302,2023, 3.1.5]
3.1.7
node profile
description of objects implemented in each node
[SOURCE: ISO/IEC 14543-4-302:2023, 3.1.6]
3.1.8
remote control
control from outside the home
[SOURCE: ISO/IEC 14543-4-302:2023, 3.1.9]
3.1.9
response wait time
time between a controller request to an electric vehicle supply equipment charger and
discharger and the response from an electric vehicle supply equipment charger and discharger
3.1.10
super class
properties that are inherited and implemented in all device objects
[SOURCE: ISO/IEC 14543-4-302:2023, 3.1.11]
3.2 Abbreviated terms
AC alternating current
DC direct current
DNOJ destination NECD object
EV electric vehicle
EVSE electric vehicle supply equipment
IP internet protocol
NDATA NECD data
NDT NECD property value data
NECD network enhanced control device
NHD NECD header
NPC NECD property code
NSV NECD service
OPC object property counter
PDC property data counter
SNOJ source NECD object
TID transaction ID
UDP user datagram protocol
4 Conformance
EVSE charger and dischargers and controllers of HES Class 1 that claim conformance to this
document shall:
– send, receive, and process sequences and procedures as specified in Clause 7.
– provide application services and properties specified in 6.2, 6.3, and 6.4 as needed by EVSE
charger and dischargers and controllers for which the application is intended.
5 Configuration
This document is necessary for ensuring interoperability between the products of different
manufacturers in connection with application communications between EVSE charger and
dischargers and controllers, using the NECD protocol as an application protocol via UDP (TCP)
and IPv6 communications.
Figure 2 shows the physical configuration in this document and the path and direction of
electricity and communication. As shown in Figure 2, this document considers the electricity
that is transferred both from home or grid to EV and from EV to home or grid. This document
does not specify any requirement about the connector, data, and electricity between EV and
EVSE. Any type of connector, data, and electricity can be used between EV and EVSE that are
referred to in this document.
Figure 2 – Physical configuration, and the path and direction
of electricity and communication
Figure 3 shows the configurations assumed in this document.

a
"Electric vehicle charger/discharger class object" is a device object specified in IEC 62394.
Figure 3 – Connection configurations
The upper illustration in Figure 3 shows the case where a single device object is installed in a
single node. The lower illustration shows the case where multiple device objects are installed
in a single node. The latter case occurs when multiple EVSE charger and discharger units are
attached to a single communications unit. In this case, there are multiple electric vehicle
charger/discharger class objects in a single EVSE charger and discharger node (i.e. at a single
IP address). Controllers shall support nodes that configure multiple device objects in a single
node.
Controllers shall be capable of handling multiple nodes and objects. The maximum number of
nodes and objects to be handled is implementation-dependent on the controllers. In the
environment where multiple controllers exist in the same network, an EVSE charger and
discharger shall respond to the latest command from any controller.
Figure 4 shows the assumed network stack for operating the NECD protocol in this document.
NECD protocol operation is assumed as an application protocol on UDP(TCP) and IPv6.
TCP installation is optional. As a rule, the stack uses IPv6; however, IPv4 is allowed depending
on the market trends for migration from IPv4 to IPv6.
ISO/IEC 14543-4-304
Application layer IEC 62394
ISO/IEC14543-4-3
Transport layer UDP(TCP)
Network layer IPv6 or IPv4
a
(Adaptation layer) (6LoWPAN )
MAC layer (No specific MAC layer assumed)
PHY layer (No specific PHY layer assumed)

a
Depends on transmission media using IPv6.
Figure 4 – Assumed network stack
Connection processing specific to each lower layer communications medium that is necessary
in advance of the start of NECD communications is out of the scope of this document. In this
document, application communications using the NECD protocol are specified on the
assumption that connection processing specific to those communications media is complete.
6 Application layer
6.1 General
The NECD protocol shall be used at the application layer. All nodes that conform to this
document shall support all mandatory functions specified in ISO/IEC 14543-4-3.
6.2 NECD objects
EVSE charger and dischargers shall have the NECD objects shown in Table 1. Controllers shall
have the NECD objects shown in Table 2.
Table 1 – NECD objects for EVSE charger and dischargers
Class group
NECD object Class code Class name Instance code
code
Electric vehicle
0x02 0x7E 0x01 to 0x7F
EVSE charger and
charger/discharger
discharger
0x0E 0xF0 Node profile 0x01
NOTE 1 Instance code 0x00 is designated to specify all instances of the same class in a node.
Table 2 – NECD objects for controllers
Class group
NECD object Class code Class name Instance code
code
0x05 0xFF Controller 0x01 to 0x7F
Controller
0x0E 0xF0 Node profile 0x01
NOTE 2 Instance code 0x00 is designated to specify all instances of the same class in a node.
6.3 NECD services
EVSE charger and dischargers and controllers shall support the NECD services shown in
Table 3.
Table 3 – NECD services
NSV code NECD service content Symbol Sender
0x51 Property value write "response-not-possible" response SetC_SNA EVSE charger
and discharger
0x52 Property value read "response-not-possible" response Get_SNA EVSE charger
and discharger
0x61 Property value write request (response required) SetC Controller
0x62 Property value read request Get Controller
0x71 Property value write response Set_Res EVSE charger
and discharger
0x72 Property value read response Get_Res EVSE charger
and discharger
0x73 Property value notification INF Controller and
EVSE charger
and discharger
6.4 Object-specific NECD properties
EVSE charger and dischargers shall install the NECD properties of a device object shown in
Table 4 and Table 5. NECD properties of a node profile object shall support at least the
mandatory properties.
Controllers shall send requests to the device object properties shown in Table 4 and Table 5.
Table 4 – NECD properties of device object (super class)
Access rule
Announcement at
Property name NPC Units Remarks
status change
Get Set
Installation location 0x81 － M M M
Standard version information 0x82 － M － －
Identification number 0x83 － O － －
Fault status 0x88 － M － M
Manufacturer code 0x8A － M － －
Status change announcement
0x9D － M － －
property map
Set property map 0x9E － M － －
Get property map 0x9F － M － －
M: mandatory, O: optional, －: not supported

Table 5 – NECD properties of device object
Access rule
Announcement at
Property name NPC Units Remarks
status change
Get Set
Operation status 0x80 － M － M
Dischargeable capacity of vehicle
a, b, g
0xC0 Wh M － －
mounted battery 1
Remaining dischargeable capacity of
a, c, g
0xC2 Wh M － －
vehicle mounted battery 1
Remaining dischargeable capacity of
c, g
0xC4 % M － －
vehicle mounted battery 3
a
－ －
Rated charge capacity 0xC5 W M

a
Rated discharge capacity 0xC6 W M － －

Vehicle connection and
0xC7 － M － M
chargeable/dischargeable status
Minimum/maximum charging electric
a
0xC8 W M － －
power
Minimum/maximum discharging electric
a
0xC9 W M － －
power
a
Minimum/maximum charging current 0xCA 0.1A M － －

a
Minimum/maximum discharging current 0xCB 0.1A M － －

Charger/discharger type 0xCC － M － －
d
Vehicle connection confirmation 0xCD － － M －

Chargeable capacity of vehicle
a, b
－ －
0xCE Wh M
mounted battery
Remaining chargeable capacity of
a, b
－ －
0xCF Wh M
vehicle mounted battery
Used capacity of vehicle-mounted
a, b, g, h
0xD0 Wh M － －
battery 1
e
Operating mode setting 0xDA － M M M

Charging method 0xDC － M O M
Discharging method 0xDD － M O M
Remaining stored electricity of vehicle-
a, f, g
0xE2 Wh M － －
mounted battery 1
Remaining stored electricity of vehicle-
f, g
0xE4 % M － －
mounted battery 3
Vehicle ID 0xE6 M － －
M: mandatory, O: optional, －: not supported
a
These properties are calculated as AC.
b
These properties are mandatory only when applicable information is provided by the EV that connects to the
EVSE charger and discharger. When the EVSE charger and discharger cannot reply, the EVSE charger and
discharger shall reply Get_SNA [0x52].
c
One of them is mandatory when applicable information is provided by the EV that connects to the EVSE charger
and discharger.
d
This property is mandatory only when property value of "Charger/discharger type" property [0xCC] is "DC_type
AA (charging only)" (0x21), "DC_type AA (charging/discharging possible)" (0x22), or "DC_type AA (discharging
only)" (0x23).
e
When EVSE charger and discharger receives a write request of property value "Preparation" (0x48) from
controllers, the EVSE charger and discharger shall not renew its property value to "Preparation" (0x48).
f
One of them is mandatory when applicable information is provided by the EV that connects to the EVSE charger
and discharger.
g
The number at the end of the property name (1 or 3) does not express the difference of the physical battery
but expresses the difference of the unit. "1" is expressed in watt-hours (Wh) and "3" is expressed as a
percentage (%).
h
"Used capacity" is the same as "useable capacity".

The details of the properties shown in Table 4 and Table 5 are specified in IEC 62394 "Electric
vehicle charger/discharger class specifications". If a discrepancy between IEC 62394 and this
document exists, the description in this document applies.
The properties shown in Table 4 and Table 5 are used for energy management and other
general purposes, and therefore should not be relied on for billable purposes.
The NECD properties shown in Table 5 involving measurements are expressed in AC units
whether the EVSE charger and discharger exchanges AC power with EV or exchanges DC
power with EV.
Fault status of EVSE charger and dischargers shall be shown in "Fault status" property [0x88]
as true or false. EVSE charger and dischargers can describe details of the fault status by using
other fault NECD properties ("Manufacturer’s fault code" property [0x86] and "Fault description"
property [0x89]) as specified in IEC 62394.
6.5 Application operation
6.5.1 General
6.5.2 to 6.5.7 specify the operations on EVSE charger and dischargers and controllers at the
application level.
6.5.2 Continuous requests
A request from a controller and the corresponding response from an EVSE charger and
discharger is a basic unit of communications, i.e. an EVSE charger and discharger returns a
single response to a single request. Controllers that issue continuous requests to an EVSE
charger and discharger shall be designed with a response wait time defined in Table 6. When
receiving a response, the time is reset, and the controller can send a new request.
If a controller resends or continuously sends requests in an interval shorter than a response
wait time value specified in Table 6, it is possible that EVSE charger and dischargers do not
accept the requests, do not renew the values to respond, or are not able to renew the values
correctly. "Continuous requests" means continued requests to the same EVSE charger and
discharger node, not to the same EVSE charger and discharger instance.
6.5.3 Response wait time value for controllers
The values of response wait times, which count the time from a controller’s request until the
response from the targeted EVSE charger and discharger, are specified in Table 6.
Table 6 – Response wait time values for controllers
Parameter name Value
Response wait time At least 20 [s]

EVSE charger and dischargers shall respond within the time specified in Table 6, in case the
received request’s OPC is 1 or in case the EVSE charger and discharger processes operations
specified in Clause 7 only. In case the request’s DNOJ instance code is all-instance designation
code [0x00], the targeted EVSE charger and discharger shall return the first response frame
within the time specified in Table 6.
6.5.4 Resending a frame
If a controller sends a request to an EVSE charger and discharger and does not receive the
response from the EVSE charger and discharger within the response wait time value specified
in Table 6, the frame shall not be retransmitted in a frame of the same TID. In this case
controllers may resend a message with a different TID.
6.5.5 Processing object property counter
EVSE charger and dischargers shall be capable of supporting OPC value of 8 or more. EVSE
charger and dischargers shall process operations with an OPC value of 8 as specified in
Clause 7 only. EVSE charger and dischargers are not required to process operations with any
combination of NPCs up to 8.
The order of NPCs of the response to a request with multiple NPCs shall be the same as the
request.
6.5.6 Property values of write requests
When controllers issue a SetC [0x61] request, a value outside the range of properties required
by IEC 62394 shall not be set.
EVSE charger and dischargers shall send Set_Res [0x71] as an acceptance response anytime,
even when the set value is not within the defined range of IEC 62394.
Responses from EVSE charger and dischargers are acceptance responses. Therefore,
controllers should check EVSE charger and discharger status after receiving Set_Res [0x71],
using a Get [0x62] request to EVSE charger and dischargers.
6.5.7 Property values of read requests
EVSE charger and dischargers shall respond Get_SNA [0x52] for Get [0x62] request of
"Dischargeable capacity of vehicle mounted battery 1" property [0xC0], "Remaining
dischargeable capacity of vehicle mounted battery 1" property [0xC2], "Remaining
dischargeable capacity of vehicle mounted battery 3" property [0xC4], "Chargeable capacity of
vehicle mounted battery" property [0xCE], "Remaining chargeable capacity of vehicle mounted
battery" property [0xCF], "Used capacity of vehicle-mounted battery 1" property [0xD0],
"Remaining stored electricity of vehicle mounted battery 1" property [0xE2], and "Remaining
stored electricity of vehicle mounted battery 3" property [0xE4] from controllers when EVSE
charger and dischargers do not connect with EV, or when property value of "Vehicle connection
and chargeable/dischargeable status" property [0xC7] is "Undetermined", and property value of
"Charger/discharger type" property [0xCC] is "DC_type AA (charging only)" (0x21) or "DC_type
AA (charging/discharging possible)" (0x22) or "DC_type AA (discharging only)" (0x23) or
"DC_type BB (charging only)" (0x31) or "DC_type BB(charging/discharging possible)" (0x32) or
"DC_type BB (discharging only)" (0x33) or "DC_type EE(charging only)" (0x41) or "DC_type EE
(charging/discharging possible)" (0x42) or "DC_type EE (discharging only)" (0x43) or "DC_type
FF (charging only)" (0x51) or "DC_type FF (charging/discharging possible)" (0x52) or "DC_type
FF (discharging only)" (0x53).
Controllers shall obtain the property value of "Charger/discharger type" property [0xCC] and
"Operating mode setting" property [0xDA] from each target EVSE charger and discharger.
7 Normal operation
7.1 General
Clause 7 specifies the normal operation sequence between EVSE charger and dischargers and
controllers.
Figure 5 shows the summary of normal operation sequences between an EVSE charger and
discharger and a controller. Here, the connection process of the lower-layer network between
an EVSE charger and discharger and a controller is assumed completed.

Figure 5 – Summary of normal operation sequences
7.2 Start-up operation
7.2.1 General
7.2.2 to 7.2.5 specify the operations on EVSE charger and dischargers and controllers at start-
up.
7.2.2 Start-up processing of NECD nodes
After establishing a connection to a lower-layer network, EVSE charger and dischargers and
controllers notify each instance list.
Instance list notification may include:
a) one node and one instance;
b) one node and multiple instances of a class;
c) one node and instances of multiple different classes.
In any case, controllers shall recognize the devices to be managed upon receiving an instance
list notification.
– Target property of node profile object
• 0xD5: Instance list notification
7.2.3 Search processing
Controllers shall have a process to search EVSE charger and dischargers in preparation for
cases where controllers fail to receive the instance list notifications sent from EVSE charger
and dischargers at start-up. Controllers shall send Get [0x62] via multicast with DNOJ as
electric vehicle charger/discharger object, with all-instance designation code [0x00], and with
"Operation status" property [0x80]. Alternatively, controllers may send Get [0x62] via multicast
with DNOJ as node profile object [0x0EF001] and its "Self-node instance list S" property [0xD6].
– Target property of electric vehicle charger/discharger object
• 0x80: Operation status
7.2.4 Obtaining NECD attribute information
After receiving instance list notifications from EVSE charger and dischargers or after completing
a search for EVSE charger and dischargers, controllers request NECD attribute information
necessary for NECD communications. Controllers may re-obtain the NECD attribute information
if necessary.
Controllers should confirm "Standard version information" property [0x82] and properties
installed on EVSE charger and dischargers based on the NECD attribute information, and then
should issue requests to the installed properties.
– Target properties of electric vehicle charger/discharger object
• 0x82: Standard version information
• 0x9D: Status change announcement property map
• 0x9E: Set property map
• 0x9F: Get property map
– Sequence
Figure 6 shows the sequence for obtaining NECD attribute information.
• Controller requests four target properties (in any combination or in any order) by Get
[0x62], after receiving an instance list notification from the target EVSE charger and
discharger.
• EVSE charger and discharger shall return Get_Res [0x72].
Figure 6 – Sequence for obtaining NECD attribute information
7.2.5 Obtaining EVSE charger and discharger attribute information
After receiving NECD attribute information from EVSE charger and dischargers, controllers
request attribute information, etc. from EVSE charger and dischargers. Controllers may
re-obtain the EVSE charger and discharger attribute information if necessary.
– Target properties of electric vehicle charger/discharger object
• 0x83: Iden
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