ISO 8714:2023

INTERNATIONAL ISO
STANDARD 8714
Second edition
2023-07
Electric road vehicles — Reference
energy consumption and range — Test
procedures for passenger cars and
light commercial vehicles
Véhicules routiers électriques — Consommation d'énergie de
référence et autonomie de référence — Modes opératoires d'essai
pour voitures particulières et véhicules utilitaires légers
Reference number
© ISO 2023
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ii
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Abbreviated terms . 2
5 Test sequence . 2
5.1 General . 2
5.2 Selection of ADT cycle . 2
5.3 Deviations in speed trace for vehicles with less maximum speed than the
maximum speed of the selected ADT cycle . 2
5.4 Selection of the number of ADT cycles for the shortened test . 3
5.5 Speed determination and procedure for running a CSS . 3
6 Tolerances . 3
7 End-of-test criteria . 4
8 Measurement of range and energy consumption . 5
8.1 General . 5
8.2 Parameters, units and accuracy of measurements . 5
8.3 Test conditions . 6
8.3.1 Vehicle conditions . 6
8.3.2 Ambient temperature conditions . 6
8.4 Test procedure . 6
8.4.1 General . 6
8.4.2 Charging of the RESS . 7
8.4.3 Application of the designated test sequence and calculation for results . 8
8.4.4 Test procedure overviews . 11
9 Presentation of results .11
Annex A (informative) Test results of reference energy consumption and range of test
vehicle . .12
Annex B (normative) Determination of CSS speed .14
Bibliography .18
iii
Foreword
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www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 22, Road vehicles, Subcommittee SC 37,
Electrically propelled vehicles.
This second edition cancels and replaces the first edition (ISO 8714:2002), which has been technically
revised.
The main changes are as follows:
— addition of shortened test;
— deletion of the former Annexes A, B and C (regional tests) because their information is obsolete.
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
INTERNATIONAL STANDARD ISO 8714:2023(E)
Electric road vehicles — Reference energy consumption
and range — Test procedures for passenger cars and light
commercial vehicles
1 Scope
This document specifies test procedures for measuring the reference energy consumption and
reference range of purely electrically propelled passenger cars and commercial vehicles of a maximum
authorized total mass (in accordance with ISO 1176) of 3 500 kg and a maximum speed of 70 km/h or
more.
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/TR 8713, Electrically propelled road vehicles — Vocabulary
ISO 8715, Electric road vehicles — Road operating characteristics
ISO 10521 (all parts), Road vehicles — Road load
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO/TR 8713 and the following
apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
complete electric vehicle kerb mass
mass of the electric vehicle including the rechargeable energy storage system (RESS), without
occupants or load, but with combustion heater fuel, cooling liquid, window-washer fluid, lubricating oil,
tools and spare wheel, and on-board charger and portable charger or part of it, if provided as standard
equipment by the vehicle manufacturer
Note 1 to entry: Adapted from ISO 8715.
3.2
reference energy consumption
quantity of electrical energy from the external AC electric power source needed to recharge the
rechargeable energy storage system (RESS), divided by the distance covered or calculated, after the
vehicle has been driven through a specified test sequence
Note 1 to entry: The reference energy consumption is usually expressed in watt-hours per kilometre (Wh/km).
3.3
reference range
distance covered by or calculated for an electric vehicle over a designated test sequence on a fully
charged rechargeable energy storage system (RESS), to the end of the test sequence as defined by the
end-of-test criteria
Note 1 to entry: The reference range is usually expressed in kilometres (km).
3.4
test mass
sum of the complete electric vehicle kerb mass (3.1) plus the maximum authorized pay mass (including
driver) if it is equal or less than 180 kg; 180 kg, if the maximum authorized pay mass exceeds 180 kg
but is less than or equal to 360 kg; half of the maximum authorized pay mass if this pay mass exceeds
360 kg
4 Abbreviated terms
ADT applicable driving test
CCT consecutive cycle test
CSS constant speed segment
RESS rechargeable energy storage system
5 Test sequence
5.1 General
There are two test methods for measuring the reference energy consumption and reference range
of purely electrically propelled vehicles on a chassis dynamometer, the consecutive cycle test (CCT)
(see 8.4.3.2) and the shortened test (see 8.4.3.3). The CCT repeats the selected applicable driving test
(ADT) cycle (see 5.2) as a test sequence until the end-of-test criterion is reached (see Clause 7). The test
sequence of the shortened test consists of a selected number of ADT cycles (see 5.2 and 5.4) followed
by a constant speed segment (CSS) (see 5.5). The CSS is performed for discharging the RESS by a higher
electrical load than the average ADT cycle load in order to shorten the overall test duration.
The RESS discharging in the shortened test shall be performed by running the vehicle in a CSS or
optionally with a constant power discharge via the DC fast charging port (see 5.5).
5.2 Selection of ADT cycle
Select a relevant regional ADT cycle for the definition of the test sequence. The selected ADT cycle
applies to either CCT in 8.4.3.2 or shortened test in 8.4.3.3.
The same test sequence shall be used to define energy consumption and range. Every effort shall be
made to conduct the tests by following the reference curve within the tolerances given in Clause 6, see
Figure 1.
5.3 Deviations in speed trace for vehicles with less maximum speed than the maximum
speed of the selected ADT cycle
Vehicles with a maximum speed capability that is less than the maximum speed of the selected ADT
cycle shall be operated at fully activated accelerator control when the speed trace cannot be followed.
Speed trace violations according to Clause 6 under this circumstances shall not void a test, if the vehicle
speed is higher than 70 km/h. Deviations from the driving cycle shall be recorded.
NOTE If the relevant regional ADT standard, where the selected regional ADT cycle belongs to, includes
requirements for a reduced test procedure for vehicles which cannot follow the target speed curv
...