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68 E L EC TR I C AL CONNEC T I ON
W I N T E R 20 1 6
SETTING A NEWSTANDARD
A
S/NZS 4777.1 was last updated
in August 2013. It went to
public comment at the time but
was held back from publication until
the current AS/NZS 4777.2, which
addresses inverter requirements, was
published. As Glen Morris puts it, ‘it
was a chicken and egg type scenario.’
Glen, who is a member of a number
of key industry advisory and regulatory
committees including EL-42 (the
committee responsible for maintaining
the Australian Standards for PV
design and installation) explains that
part two is the more controversial of
the Standards because it deals with
inverter requirements. Because the
requirements directly affect utility
networks, all utilities needed to agree on
the update before it could be published.
“We very nearly had the project
cancelled on us because it came up
to within five years of when it was
started and that’s the limit Standards
Australia has set for projects – so we
had to really put our heads down and
only got it finished with a few weeks
to go,” says Glen.
Part two has now been published
and will come into effect on 10
October this year. This will have some
fairly pronounced ramifications, most
notably that many existing inverters
will no longer be compliant.
“The inverter requirements for
compliance to the International
Electrotechnical Commission (IEC)
standards, and other mandatory
features that are specified in 4777.2,
will change when the new standard
comes into force. So you wouldn’t
want to stock up on inverters on 9
October, you’d probably find that
half of them fall off the Clean Energy
Council (CEC) list. Most of the specified
features are things that make inverters
more network friendly. This means
more solar can be installed with be
less objections based on the size of
systems,” says Glen.
Now that part two is out, part one
is expected to be published later this
year. The process is taking longer than
usual because it’s a joint Standard –
not just an Australian Standard – and
as such must undergo a formal process
at the New Zealand end that can take
a few months.
When the new Standard comes into
force, it’ll bring with it some significant
changes that contractors will have to
adopt into their business models. These
will include new signage requirements
and also a lot of changes relating to
hybrid or multi-mode inverters.
“Essential circuits supplied
independently in standalone mode
will have to be connected to a
dedicated switchboard – not a sub-
set of a grid switchboard. So that will
make things a bit more complicated in
small installations where the customer
has got a switchboard in their
hallway, for example, and they want
a hybrid system installed. In this
situation the contractor is going to
have to explain that the customer
needs to put another switchboard in
as well,” says Glen.
Phase balancing requirements is
another area that has been updated,
stipulating that generation over 5kVA
must be across three phases – meaning
the end of 10kVA systems on single
phase supplies.
“We are updating the anti-islanding
set point to be more gradual. At the
moment the passive anti-islanding
features are very crude tools. To
counter this, we’ve allowed for a rate
of change over time for voltage and
for frequency to smooth out and
randomise the effects of passive
anti-islanding,” says Glen.
In an effort to facilitate smart grid
functionality, the update also makes
new provisions for demand response
modes. Smart grid is about the grid
acting as an autonomous system
without the need for lots of individual
controls and demand response modes
are a step towards that goal.
To comply with the new Standard,
all inverters must have demand
response modes available and
installers will be required to mark on
the side of the inverter which modes
have been enabled.
Demand response modes are
AS/NZS 4777.1 IS THE PRIMARY
STANDARD RELATING TO THE
SAFETY AND INSTALLATION OF
GRID-CONNECTED PV SYSTEMS
WITH OR WITHOUT STORAGE –
AND IT’S CHANGING. AUSTRALIAN
SOLAR COUNCIL VICE PRESIDENT
GLEN MORRIS SPOKE TO
JACOB
HARRIS
TO EXPLAIN HOW.
SOLAR
Part two has now been published and will come into
effect on 10 October this year. This will have some
fairly pronounced ramifications, most notably that
many existing inverters will no longer be compliant.