With the WA Government’s recent announcement of the fast-charging electric vehicle network, we expect an increasing number of applications for installing and connecting vehicle charging stations.
When installing electric vehicle charging stations, electrical contractors must ensure that they do not exceed the capacity of the supply and connection arrangement.
Specific attention is needed for residential and small commercial connections that have a standard connection service. This is to ensure the connection remains safe and compliant.
What is defined as standard supply?
The Western Australian Service and Installation Requirements (WASIR) defines standard supply as 240 volt single-phase (+/- 6%) or 415 volt three-phase (+/- 6%). This varies depending on location as shown below:
Perth metropolitan and major regional centres within the SWIS:
- 63 amps single-phase (240 volts); or
- 32 amps per phase, three-phase (415 volts); and
Rural centres and connections within the SWIS (*Note 1):
- 32 amps single-phase (240 volts); or
- 32 amps per phase, three-phase (415 volts) or
- 16 amps per phase, multi phase, (480 volts); and
- maximum size of consumer mains cable shall not exceed 35mm2
The Western Australian Electrical Requirements (WAER) also state that the minimum sized consumer mains cable for domestic premises must be in accordance with clause 9.2:
- single-phase: 10 square millimetres, copper conductors; or
- three-phase: 6 square millimetres, copper conductors.
To determine the maximum demand, refer to AS/NZS 3000:2018, specifically:
- clause 2.2.2 maximum demand, and
- appendix C, circuit arrangements and clause C2 maximum demand (with reference to tables C1 and C2 for single and multiple domestic and commercial electrical installations).
When must you upgrade to a standard connection service?
For EV charging connections, the consumer(s) main switch must be upgraded to a circuit breaker rated for a standard connection service if:
- the capacity exceeds the supply arrangement rating;
- is unknown; or
- the connection is a network mini pillar or pit.
In all cases, an application must be made to Western Power to accommodate any requested additional load above a standard connection service. View our information on modifying your power supply for further details on this process.
Please contact WA Electrical Inspectors if you have any queries.
* Note 1
Subject to service availability. For network connection generation capacity limits, refer to WASIR Section 15 and Western Power’s embedded generation requirements.