BS EN 50618

Title: Electric cables for photovoltaic systems

Introduction to BS EN 50618

The BS EN 50618 standard covers low smoke halogen-free, flexible, single-core power cables with crosslinked insulation and sheath. They are intended for use on the direct current (d.c.) side of photovoltaic systems, with a nominal d.c. voltage of 1.5 kV between conductors and between conductor and earth.
The cables are suitable to be used with Class II equipment.
The cables are designed to operate at a normal maximum conductor temperature of 90 °C but for a maximum of 20,000 hours max. conductor temperature of 120 °C at a max. ambient temperature of 90 °C is permitted.

BS EN 50618 cables are designed to be suitable for permanent outdoor use for many years under variable demanding climate conditions. Relatively stringent requirements are set in this standard, for these products, in line with the expected harsh usage conditions.
NOTE The expected period of use under normal usage conditions as specified in this standard is at least 25 years.

Rated voltage

The cables specified in the BS EN 50618 standard are, in particular, designed for use at the direct current (d.c.) side of photovoltaic systems, with a nominal d.c. voltage of 1.5 kV between conductors as well as between conductor and earth. The maximum permitted operating d.c. voltage of the systems in which the cables specified in this standard are applied shall not exceed 1,8 kV.

The cables have a rated voltage of 1,0/1,0 kV when used in alternating current (a.c.) systems.

Annex A of the BS EN 50618 standard gives additional guidance on voltage ratings.

Construction

• BS EN 50618 standard specifies the use of tin coated class 5 copper conductors and in accordance with EN 60228.
• The insulation and sheathing materials specified are cross-linked, full details of which are given in Annex B.
• The insulation and sheath are to be applied by extrusion.

NOTE: Insulation applied in more than one layer does not conform to the definition of “Double insulation” given, for instance, in HD 60364.

BS EN 50618 standard designates these cables with the following core ‘H1Z2Z2-K’.

The size range included in the standard is 1,5 mm2upto and including 240 mm2

Table A.3 of the standard gives current carrying capacity for these PV cables