The IET solar PV code of
practice: what this means for
you
Jonny Williams
Director, BRE National Solar Centre
Martin Cotterell
Founder and Technical Director, Sundog Energy
Chris Roberts
Solar Specialist, STA
Griff Thomas
Managing Director, GTEC Training
IET Solar PV Code of Practice
© NSC 2014
Part of the BRE Trust
Introduction
Jonny Williams
IET Solar PV Code of Practice
© NSC 2014
Part of the BRE Trust
Martin Cotterell
 MCS – PV & roofing working groups
 IEC - TC82 WG3 (co-convenor)
 British Standards – chair of PV committee
 NSC - associate consultant
 Sundog Energy - founder & director
Why a new document?
 First PV specific document released by IET
 Previous UK documents only went up to 50kWp
 To align with international standard work
 New technology
 Experience
Why not wait for IEC?
Work underway …
 Part 7-712 of IEC 60364 (and BS 7671) Requirements for
special installations or locations – Solar photovoltaic (PV)
power supply systems. Recent meeting in Birmingham
 IEC 62548 Photovoltaic (PV) Arrays – Design Requirements
CD of new version recently issued – meeting in December
But slow progress gaining agreement on best approach
2002
First edition of the “DTI Guide”
2006
2nd Edition published
2007
MIS3002 published - refers to PV guide
2012
MCS PV Guide issued
2013
IET starts work on PV CoP
2014
IET issues CoP for public comment
Evolution
Scope …
“This Code of Practice sets out the requirements for the design, specification, installation,
commissioning, operation and maintenance of grid-connected solar photovoltaic (PV) systems
installed in the UK. The scope of this Code of Practice covers:
•
All parts of a grid-connected solar PV system up to, and including, the connection to the AC mains.
•
LV and HV connections and components.
•
All scales of application, from small domestic systems to large-scale PV farms.
•
Building-mounted, building-integrated and ground-mounted systems.
•
Grid-connected systems with battery storage.
•
Systems with an open circuit DC voltage of greater than 30VDC and less than 1,500VDC.
Much of the technical content of the CoP is pretty similar to the existing PV Guide
New sections …
 Large systems
 HV connections
 Grid connected systems with battery storage
 LPS & surge protection
 Fire
Much of the technical content of the CoP is pretty similar to the existing PV Guide
Headline changes …
 Array frame earthing
 Earth fault alarm
 String fuses
 PV plug & sockets
Much of the technical content of the CoP is pretty similar to the existing PV Guide
What's NOT included …
 MCS scheme requirements
 Specific energy estimate procedure
Array frame earthing …
It is proposed that the PV array
frame will now need an earth
connection in most circumstances
Array frame earthing …
o
Allows DC isolation fault detection systems to operate correctly (provided in most inverters)
o
Minimises the shock risk due to leakage currents on systems with transformer-less inverters
o
Brings the UK in line with the approach taken in most other countries around the world
(and IEC standards/documents).
Earth fault alarm …
“The Earth fault alarm shall:
a)
b)
c)
continue to operate until the system is switched off or the fault is
corrected;
be of a type that can’t be missed (for example, visible/audible signal in
a public area, or SMS message); and
be accompanied with instructions to the system operator on the need
to immediately investigate the fault.”
Fault detection
+ fire prevention
More than just an LED on an inverter …
String fuses …
Proposed that these will only now be
required on one of the active
conductors
Plug and sockets …
proposed to ban mating of different
manufacturer’s / models
This session too short
comprehensive overview
for
a
The previous slides … just the
headlines
This is a draft document, please:
 download
 read
 comment
Griff Thomas (MD GTEC)
Contract reconciliation
Expert witness reports
Regulatory compliance audits
The creating of the Code of Practice is nearing
completion and comments are due back in by
November 7th
Once finalised the sector needs to make a
decision over how it can best be put to use
The question is:
Contract reconciliation
Expert witness reports
Regulatory compliance audits
How should the Code of Practice
best be implemented in the
sector to ensure that it adds value
to contractors and clients?
Contract reconciliation
Expert witness reports
Regulatory compliance audits
The implementation in any form should serve
to:
Increase safety
Standardise installation practices
Provide customer / investor assurance
Minimise technical barriers to PV
deployment
 Minimise legislative barriers to PV
deployment (possible ROOFIT access?)




Contract reconciliation
Expert witness reports
Regulatory compliance audits
As with any technical standard a decision must
be made as to how it can be used to best
serve the sector concerned
As a “Code of Practice” there are a number of
options open to the industry broadly as
follows:
Contract reconciliation
Expert witness reports
Regulatory compliance audits
Optional conformance
Contractors may choose to work to the
standard and self-declare and promote this to
their customers
No 3rd party verification is likely to take place
unless the customer requests it
Contract reconciliation
Expert witness reports
Regulatory compliance audits
Optional conformance with regulatory
recognition
Contractors may choose to work to the
standard and self-declare and promote this to
their customers
Regulatory bodies are persuaded to recognise
conformance to the Code of Practice (OfGEM)
Contract reconciliation
Expert witness reports
Regulatory compliance audits
A Stand Alone Certification Scheme
A new scheme is created that focusses on the
Code of Practice and promotes the benefit of
the certificated contractor the industry
Contract reconciliation
Expert witness reports
Regulatory compliance audits
An Addition To An Existing Certification
Scheme
There are a number of “approved contractor”
schemes already operation in the sector,
consider adding certification to one of these
as an option for the contractor and obtain
regulatory recognition
Contract reconciliation
Expert witness reports
Regulatory compliance audits
The options presented are by no means hard
and fast and a number of permutations are
possible
It is over to the sector to now decide how they
feel that the Code of Practice could be
integrated to ensure that it adds value to their
work
Contract reconciliation
Expert witness reports
Regulatory compliance audits
Over to you…………….
Contract reconciliation
Expert witness reports
Regulatory compliance audits