ISO 20766-1:2018

INTERNATIONAL ISO
STANDARD 20766-1
First edition
2018-11
Road vehicles — Liquefied petroleum
gas (LPG) fuel systems components —
Part 1:
General requirements and definitions
Véhicules routiers — Équipements pour véhicules utilisant le gaz de
pétrole liquéfié (GPL) comme combustible —
Partie 1: Exigences générales et définitions
Reference number
©
ISO 2018
© ISO 2018
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Published in Switzerland
ii © ISO 2018 – All rights reserved

Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 Construction and assembly . 5
5 Electrical equipment and wiring . 6
6 Instructions . 6
7 Marking . 7
Bibliography . 8
Foreword
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URL: www .iso .org/iso/foreword .html
This document was prepared by Technical Committee ISO/TC 22, Road vehicles, Subcommittee SC 41,
Specific aspects of gaseous fuels.
A list of all parts in the ISO 20766 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
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iv © ISO 2018 – All rights reserved

INTERNATIONAL STANDARD ISO 20766-1:2018(E)
Road vehicles — Liquefied petroleum gas (LPG) fuel
systems components —
Part 1:
General requirements and definitions
1 Scope
This document specifies general requirements and definitions of liquefied petroleum gas fuel system
components, intended for use on the types of motor vehicles as defined in ISO 3833. It also provides
general design principles, and specifies requirements for instructions and marking.
This document is applicable to vehicles (mono-fuel, bi-fuel or dual-fuel applications) using gaseous fuels
in accordance with ISO 9162. It is not applicable to the following:
a) fuel containers;
b) stationary gas engines;
c) container mounting hardware;
d) electronic fuel management; and
e) refuelling receptacles.
NOTE 1 It is recognized that miscellaneous components not specifically addressed herein can be examined
for compliance with the criteria of any applicable part of ISO 20766, including testing to the appropriate
functional tests.
NOTE 2 All references to pressure in this document are considered gauge pressures unless otherwise
specified.
NOTE 3 This document applies to devices which have a service pressure in the range of 110 kPa (Butane rich
at 20 °C) and 840 kPa (Propane rich at 20 °C), hereinafter referred to in this document. Other service pressures
can be accommodated by adjusting the pressure by the appropriate factor (ratio).
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 6722-1, Road vehicles — 60 V and 600 V single-core cables — Part 1: Dimensions, test methods and
requirements for copper conductor cables
ISO 6722-2, Road vehicles — 60 V and 600 V single-core cables — Part 2: Dimensions, test methods and
requirements for aluminium conductor cables
1)
ISO 20766 (all parts) , Road vehicles — Liquefied petroleum gas (LPG) fuel systems components
1) Under preparation.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— IEC Electropedia: available at http: //www .electropedia .org/
— ISO Online browsing platform: available at https: //www .iso .org/obp
3.1 Valves
3.1.1
valve
device by which the flow of a fluid can be controlled
3.1.2
manual valve
valve which is operated manually
3.1.3
remotely controlled (automatic) valve
valve which is not operated manually and controlled by Electronic control unit (ECU)
3.1.4
remotely controlled (automatic) container valve
automatic valve rigidly fixed to the container which controls the flow of gas to the fuel system and
controlled by ECU
3.1.5
non return valve or check valve
automatic valve which allows gas to flow in only one direction
3.1.6
excess flow valve
valve which automatically shuts off, or limits, the gas flow when the flow rate exceeds a set design value
3.1.7
manual container valve
manual valve rigidly fixed to the container
3.1.8
pressure relief valve
PRV
self-closing device which opens to prevent a pre-determined pressure being exceeded
3.1.9
service valve
manual valve which is closed only when servicing the vehicle
3.2 Fuels
3.2.1
liquefied petroleum gas vehicle
road vehicle powered by LPG
2 © ISO 2018 – All rights reserved

3.2.2
mono‐fuel
road vehicle which operates on liquefied petroleum gas only
Note 1 to entry: It is designed primar
...