Cables for photovoltaic installations

Solar cables are key in a photovoltaic installation, whether in large installations on solar farms or in smaller installations in domestic self consumption solar systems.

INDEX

High performance cables designed for solar installations

In large solar farms, sun energy is directly transformed into electrical energy. These cables are suitable for use at high temperatures and all kinds of weather conditions. Since the cable volume in these installations is quite high, it is essential to use the appropriate cables with the maximum performance, and make sure they comply with the new 1500V EN 50618 standard.

Solar cables from panel to stringbox

TOPSOLAR PV cable H1Z2Z2-K 1.5/1.5 (1.8) kV DC has been specifically designed to withstand the most demanding conditions between the panels and the LV DC network of a solar installation.

The H1Z2Z2-K TOPSOLAR PV cable, designed according to EN 50618 and IEC 62930 standards, consists of a tinned copper conductor (required by standards), a halogen-free insulation (LSHF) and a low-smoke rubber sheath. These are its most representative features:

	UV-resistant
	Low-smoke halogen-free cables (CPR European Construction Products Regulation: Cca -s1b, d2, a1)
	TÜV certificate
	Their admissible intensity is higher, with the same cross-section, than conventional cables, allowing conductor temperatures of up to 120ºC
	I30 years lifespan at 90ºC
	Its extraordinary flexibility and reduced diameter eases installation
	Solar cables are best for mobile service. The use of solar trackers is frequent to make the most of solar radiation. In these cases, the connection cables between the mobile structures and the fixed parts are subject to movement, making conventional cables unsuitable
	Solar cables are compatible with most renowned connectors
	They can be installed permanently immersed in water (AD8)

Medium voltage cables for solar installations:

Medium voltage and aluminium cables go from the transformer to the electrical distribution network. Top Cable can offer a wide range of Medium Voltage cables for solar farms, certified by the main electricity companies:

- XLPE cables (insulated in cross-linked polyethylene) such as the X-VOLT RHZ1 cables, which provide a great insulation resistance.

- HEPR cables (insulated with ethylene propylene), such as X-VOLT AL (-OL) HEPRZ1 (AS) cables, which withstand continuous operating temperatures of 105ºC, providing excellent resistance to thermal ageing and partial discharges.

In both cases, MV cables can include sealing elements in the screen, which prevent the longitudinal propagation of moisture in the event of outer sheath perforation and/or elements for the longitudinal sealing of the conductor.

Aluminium cables for solar installations:

TOPSOLAR PV AL 1500 V. This cable has a class 2 aluminium conductor, XLPE insulation and PVC outher sheath. It is a UV resistant cable, with an operating temperature of 90ºC and can be installed totally submerged in water (AD8).
TOPSOLAR^® PV AWA/SWA AL 1500 V. It’s an aluminium (single-core) or galvanized wire armour (multicores) cable, has a class 2 aluminium conductor, XLPE insulation and special UV resistant PVC. Has the impact resistance AG4 (High severity) and an operating temperature of 90ºC.
TOPSOLAR^® PV LSZH Al 1500 V HEAVY DUTY. This cable has a class 2 aluminium conductor, XLPE insulation and PVC outher sheath. It is a UV resistant halogen free cable, with an operating temperature of 90ºC and can be installed totally submerged in water (AD8) and can be directly buried in most soils.

Planning and designing a PV Plant

Auxiliary cables for solar farms:

Top Cable also has a wide range of cables for auxiliary installations in solar farms, such as:

Topflex H07V-K (yellow/green) (or its halogen-free version Toxfree ES07Z1-K (AS) ) for earthing all panel structures. Has been specially designed for installations that require a flexible cable.
Powerflex RV-K (or its halogen-free version Toxfree RZ1-K (AS) ) for closed circuit television and tracker engine supply systems, in the case of installation with trackers. It’s an industrial flexible cable for power transmission and can withstand damp conditions including total immersion in water (AD8).
TOXFREE ZH OUTDOOR H07Z1-K (AS) Cu/Sn. A solar grounding cable, with tinned copper conductor. Has a class 5 in flexibility, and an operating temperature of 70ºC.
FTP/UTP Category 6 cables and single-mode and multimode fiber optic cables.

Solar cables for domestic self-consumption installations

TOPSOLAR PV H1Z2Z2-K 1.5/1.5 (1.8) kV DC cable -that we saw at the beginning of this article- is, without doubt, the most suitable cable for a domestic photovoltaic installation:

For its excellent photovoltaic electrical performance and its extreme flexibility.
Because it is a halogen-free solar cable that complies with the European Construction Products Regulation (CPR: Cca -s1b, d2, a1).
Because it is TÜV certified.
Because it has a 30 years lifespan at 90ºC.

Considerations when choosing a photovoltaic wire cable

Electrical wiring is one of the photovoltaic installations key points. The correct cable selection will optimize the performance of the solar garden in the short, medium and long term.

Demanding conditions that a photovoltaic solar installation must withstand

The connection cable that connects the panels and the DC Low Voltage network in a photovoltaic solar installation has to withstand the most demanding conditions:

Have a useful life of 30 years at 90 ° C. Able to withstand up to 120 ° C permanently
Its admissible intensity must be higher, with equal section, to conventional cables.
It must be a cable suitable for mobile service. It is common to use trackers in order to maximize solar radiation. Do not forget that in these cases the connection cables between the mobile structures and the fixed parts are subject to movement. Conventional cables are not suitable.
More comfortable to install due to its extraordinary flexibility and reduced diameter. The recommended cable is formed by a class 5 flexible tinned copper conductor, high-quality ethylene propylene insulation and covered with ethyl vinyl acetate (EVA). Its small outer diameter makes the cable more manageable and occupies less space in the pipes.
Finally, it is not mandatory but it is very convenient that the photovoltaic cable offers the guarantee of the TÜV certificate.

The cable TOPSOLAR PV H1Z2Z2-K has been specifically designed for the connection of panels in solar farms, so it has all the features mentioned above.

Good dielectric strength, low loss factor, and high insulation resistance

As for the cables for Medium Voltage network in a photovoltaic installation. Whether the cable is XLPE (insulated with cross-linked polyethene) or HEPR (ethylene propylene). It is very convenient that its external semiconductor layer is separable. Given that its easy extraction is a critical factor when it comes to correctly prepare the tips of the cable for the splice manufacture or terminals. Also constituting a significant saving of time for the installer.

Medium voltage cables with XLPE insulation are characterized by good dielectric strength, low loss factor, and high insulation resistance.

Medium voltage cables insulated with HEPR rubber can withstand continuous operating temperatures up to 105 ° C. These also present very good resistance to thermal ageing and partial discharges.

In both cases, the cables can include sealing elements on the screen. These prevent longitudinal humidity propagation. In case of perforation of the cover and/or the elements for the longitudinal sealing of the conductor.

TOP CABLE, a complete supplier for solar electrical installations

Top Cable is an integral manufacturer and supplier of solar cables in photovoltaic plants of any size anywhere in the world.

Has a wide range of solar wiring. Do not hesitate to consult our catalogue and find any cable you need:

Download the Top Cable Solar catalogue here.

If you are also interested in other types of cable, you can consult our complete catalogue here.