WCA November 2015

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52 Wire & Cable ASIA – November/December 2015
Abstract
This paper will show the evolution from the first
German TUV Rheinland document 2Pfg1169/2001 to
2Pfg1990/2012 and the influence of this document to
national standards in the USA, Japan and Europe as well
as to the development of the standards Cenelec EN50618
and IEC62930.
Furthermore it will give an insight to the necessary design,
material combinations and production processes to
comply with the above stated standards.
In particular the challenge was to comply with multiple
standards, as for example the combination of UL and TUV.
An additional aspect will give an understanding to specific
testing procedures of essential compound properties
which have an impact on the expected very long operation
time of PV wires.
1 Introduction
Starting at the end of the last century the worldwide
interest in renewable energy was encouraging the PV
industry to grow significantly and this growth around the
world was irresistible.
At that time the construction of PV systems was an
expensive and long-term investment. The investors did
not know how to estimate the quality of modules, and
customers were asking for the expected lifetime of PV
modules and PV installations. There was a strong need for
a third-party assessment of safety and quality.
At this time the German TUV Rheinland started reviewing
the safety and quality of photovoltaic modules with their
own requirements.
Very soon it was clear that the module quality and module
safety was dependent on the components, but there
was a lack of standards for components considering the
requirements of PV application. This was the beginning of
the standardisation of PV wires.
2 The beginning
In 2001 the TUV Rheinland in Germany started testing
PV modules and noticed many problems because of the
cables.
Since no dedicated standard tests for these cables
existed, the TUV Rheinland created their own standard.
This was the birth of 2Pfg1169:2004.
This first standard was based on IEC60245-4:1994 (Rubber
insulated cables - rated voltages up to and including
450/750 V - Part 4: Cords and flexible cables). At that time
H07RN-F was the most used cable (rubber 60ºC–90ºC).
In this early stage of PV installations, nobody realised that
the requirements on PV cables were much higher.
2.1 First wiring failures after a few years
3 New requirements
After numerous wiring failures the PV experts recognised
that the requirements of the first Pfg 1169 /2004 had been
too low.
In 2006 a new experts group (German National Committee
Working Group 411.2.3) started to work on a new version of
the “Requirements for photovoltaic cables”.
In the first part of the work, it was a joined group of module
and cable experts. The focus was now on the period of use
of PV wires. The working group was principally involved in
following questions:
• How can we predict the lifetime of a cable?
• How many years does the lifetime of a cable have to
be?
• How is ageing of cables to be understood?
• How can we test the ageing process?
Standardisation of
PV wires and cables
2001-2014
By Faruk Yeginsoy, Leoni Struder AG
❍
❍ Figure 1: Wiring failures caused by ozone and high
temperatures