Solar Cable Procurement Guide: Specifications, Types, Sizing & Compliance

Selecting the right solar cable is an important part of photovoltaic system procurement. A cable that looks suitable by conductor size alone may still be inappropriate if its voltage rating, temperature rating, insulation system, environmental performance, certification, or connector compatibility does not match the PV application.

For procurement teams, installers, EPC contractors, distributors, and solar equipment manufacturers, the objective is not simply to buy a cable with a suitable cross-sectional area. The cable must satisfy the electrical and mechanical requirements of the PV system and comply with the standards applicable to the target market.

A professional solar cable procurement process should therefore evaluate five areas:

Cable specifications + cable type + sizing + standards + supplier capability

IEC 62930 covers single-core cross-linked insulated PV cables for the DC side of photovoltaic systems with rated DC voltage up to and including 1.5 kV, while UL Solutions identifies UL 4703 as the standard for photovoltaic wire in North American certification.

What Is a Solar Cable?

A solar cable, also called a photovoltaic cable or PV cable, is designed specifically for electrical connections within photovoltaic systems.

Unlike general-purpose electrical wire, PV cable is intended for the environmental and electrical conditions encountered in solar installations. Depending on the product and applicable standard, this can include exposure to sunlight, moisture, temperature changes, mechanical stress, and long-term outdoor operation.

A typical PV cable specification may include:

• Conductor material

• Conductor cross-sectional area

• Stranding class

• Insulation material

• Sheath or jacket material

• Rated voltage

• Temperature rating

• DC resistance

• Outer diameter

• Color

• Applicable standards

• Certification

• Packaging and marking requirements

The exact specification depends on the cable design and target market.

What Specifications Should You Check When Buying Solar Cable?

Before requesting quotations, buyers should prepare a clear technical specification.

Conductor Material

The most common conductor materials are:

• Copper

• Tinned copper

• Aluminum

Copper is widely used because of its electrical conductivity and compatibility with many PV connection systems.

Tinned copper is also widely used in PV cable constructions because the tin coating can provide additional protection to the copper conductor in demanding environments.

Aluminum can be used for specific PV applications where its lower weight and material characteristics are beneficial, but conductor, connector, and termination requirements must be evaluated as a complete system.

Conductor Cross-Sectional Area

Common metric PV cable sizes include:

• 1.5 mm²

• 2.5 mm²

• 4 mm²

• 6 mm²

• 10 mm²

• 16 mm²

• Larger sizes for specific applications

North American projects may specify conductors using AWG rather than mm².

Do not select conductor size based only on module wattage. Current, voltage, cable length, voltage drop, installation conditions, and applicable ampacity requirements must also be considered.

Conductor Construction

PV cables normally use stranded conductors to provide flexibility.

The procurement specification should identify the conductor class or construction where required.

Important parameters can include:

• Strand count

• Strand diameter

• Conductor compactness

• Material purity or grade

• DC resistance

The manufacturer's technical datasheet should be used to verify the actual conductor construction.

What Types of Solar Cable Are Available?

Solar cable should be selected according to the application and target market rather than simply by product name.

H1Z2Z2-K Solar Cable

H1Z2Z2-K is a widely recognized European PV cable designation associated with EN 50618 applications.

These cables are commonly used for photovoltaic DC connections and are designed for demanding outdoor environments.

When purchasing H1Z2Z2-K cable, buyers should verify the actual certification, conductor size, voltage rating, insulation and sheath construction, temperature performance, and manufacturer documentation rather than relying only on the product name.

UL 4703 PV Wire

For North American projects, PV wire certified according to UL 4703 is an important product category.

UL Solutions lists photovoltaic wire under UL 4703 and provides certification services for PV cable products for market access.

The actual cable marking and certification details should be checked against the intended installation and applicable code requirements.

IEC 62930 Solar Cable

IEC 62930:2017 specifies electric cables for photovoltaic systems with a voltage rating up to 1.5 kV DC. The standard covers single-core cross-linked insulated power cables with a cross-linked sheath for the DC side of PV systems. It specifies a normal continuous maximum conductor temperature of 90°C and includes provisions for cables that can contain halogens as well as halogen-free low-smoke constructions.

IEC 62930 is therefore an important reference when sourcing PV cable for international projects.

How to Choose the Right Solar Cable Size

Cable size should be determined from the electrical characteristics of the complete circuit.

The key parameters include:

Current + voltage + cable length + voltage drop + ampacity + installation conditions

A basic electrical relationship is:

I = P ÷ V

For example, a 200W load at 20V corresponds to approximately 10A.

However, a PV module's actual operating voltage and current should be taken from its datasheet, particularly:

• Vmp

• Imp

• Voc

• Isc

The nominal voltage of a battery system should not automatically be treated as the PV module operating voltage.

Why Cable Length Matters

A longer cable run produces greater conductor resistance and therefore greater voltage drop.

The simplified relationship is:

Vdrop = I × R

For a DC circuit, the complete circuit path must be considered.

This means a cable that performs satisfactorily over a short distance may require a larger conductor when the cable run becomes significantly longer.

The U.S. Department of Energy identifies cable length, bundling, bend radius, insulation selection, and cable routing as important considerations in PV DC-string cable management.

For procurement, buyers should therefore provide the supplier with:

• Expected operating current

• System voltage

• One-way cable distance

• Installation environment

• Allowable voltage drop

before finalizing conductor size.

Why Ampacity Alone Is Not Enough

A common procurement mistake is to select a cable simply because its ampacity exceeds the expected current.

Ampacity and voltage drop answer different questions.

Ampacity asks:

Can the conductor safely carry the required current under the applicable installation conditions?

Voltage-drop analysis asks:

Will sufficient voltage reach the connected equipment?

Both need to be considered.

A cable may have adequate current-carrying capacity but still produce excessive voltage loss over a long installation.

How Do Series and Parallel PV Systems Affect Cable Selection?

PV system configuration can significantly affect current and voltage.

Series Connection

When modules are connected in series:

Voltage increases while string current remains approximately at the module-string current.

Higher string voltage can reduce current for a given amount of power.

However, maximum open-circuit voltage under the applicable temperature conditions must be checked against the ratings of inverters, charge controllers, connectors, and other components.

Parallel Connection

When strings are connected in parallel:

Current increases while voltage remains approximately at the string voltage.

This increases the current that downstream conductors and equipment may need to carry.

Parallel configurations therefore require careful evaluation of conductor ampacity and overcurrent protection.

In U.S. PV systems, NEC Article 690 includes requirements concerning PV circuit current, conductor sizing, and overcurrent protection. Current project requirements should be checked against the applicable edition of the NEC and local electrical requirements.

What Voltage Rating Should a Solar Cable Have?

The cable voltage rating must be compatible with the maximum voltage of the PV circuit.

Modern PV systems can use relatively high DC voltages, including systems rated at 1500V DC.

IEC 62930 covers photovoltaic cables with rated DC voltage up to and including 1.5 kV.

For procurement, do not evaluate voltage rating based only on the normal operating voltage.

The complete design should consider:

• Maximum system voltage

• Open-circuit voltage

• Temperature effects

• Cable standard

• Equipment ratings

• Connector ratings

• Applicable electrical code

What Temperature Rating Should Solar Cable Have?

PV cable may be exposed to elevated temperatures, particularly when installed beneath modules or in locations with high solar irradiance.

Cable specifications may therefore include:

• Maximum conductor operating temperature

• Ambient temperature range

• Short-circuit temperature

• Installation temperature

For example, IEC 62930 specifies a normal continuous maximum conductor temperature of 90°C for cables within its scope, with limited operation at 120°C under the conditions defined by the standard.

The temperature rating should always be checked against the exact cable construction and applicable standard.

Why Are Solar Cable Insulation and Sheath Materials Important?

The conductor is only one component of a PV cable.

The insulation and sheath determine much of the cable's environmental and mechanical performance.

Depending on the design, PV cables may use cross-linked polymer materials selected for characteristics such as:

• UV resistance

• Weather resistance

• Temperature performance

• Flexibility

• Moisture resistance

• Mechanical durability

• Halogen-free performance where required

IEC 62930 includes cross-linked insulation and sheath constructions for PV cables and covers both halogen-containing and halogen-free low-smoke cable designs.

When procuring cable, buyers should therefore request the complete cable construction rather than only the conductor specification.

What Solar Cable Standards and Certifications Should Buyers Check?

There is no single worldwide PV cable certificate that automatically applies to every market.

The correct standard depends on the destination market and project requirements.

UL 4703

UL Solutions identifies UL 4703 as the standard for photovoltaic wire.

It is particularly relevant when supplying PV wire for North American applications.

EN 50618

EN 50618 is an important European photovoltaic cable standard.

UL Solutions states that EN 50618 covers flexible Class 5 halogen-free PV cables in sizes from 1.5 mm² to 240 mm² within the scope described by its certification service.

IEC 62930

IEC 62930 applies to photovoltaic-system cables with rated DC voltage up to 1.5 kV.

A professional procurement specification should identify the required standard instead of simply requesting “solar cable.”

What Documents Should a Solar Cable Supplier Provide?

A serious procurement process should go beyond a product quotation.

Depending on the project, buyers may request:

Technical Datasheet

Should identify:

• Conductor

• Insulation

• Sheath

• Voltage rating

• Temperature rating

• Resistance

• Dimensions

• Applicable standards

Test Reports

Test documentation should correspond to the actual product construction and certification scope.

Certificate or Certification Evidence

Verify:

• Standard

• Product family

• Manufacturer

• Model or construction

• Certification scope

• Validity where applicable

Factory Quality Documents

Depending on the project, buyers may request:

• Quality-management certification

• Inspection records

• Incoming-material controls

• Production test records

• Final inspection documentation

UL Solutions emphasizes that buyers and installers should understand the ratings, markings, certification status, and intended use of wire and cable products when determining suitability for an installation.

How to Verify Solar Cable Certification

A certificate should not be treated as proof of compliance simply because a supplier places a logo on a quotation.

Buyers should verify the relationship between:

Manufacturer → Product → Standard → Certification

Check the:

• Manufacturer name

• Product designation

• Cable construction

• Voltage rating

• Conductor size

• Certification mark

• Certification or listing information

• Testing body

• Applicable market

This is especially important when purchasing large quantities for an international PV project.

UL Solutions provides certification and product-marking resources intended to help code authorities, installers, contractors, and buyers identify certified and listed wire and cable products and understand their intended ratings and uses.

How to Evaluate Solar Cable Quality

Price should not be the only procurement criterion.

A professional quality assessment should examine the complete cable.

Conductor Quality

Verify:

• Conductor material

• Cross-sectional area

• Strand construction

• DC resistance

• Surface condition

Insulation and Sheath

Check:

• Material

• Thickness

• Diameter

• Flexibility

• Environmental performance

• Temperature rating

Electrical Performance

Review:

• Rated voltage

• DC resistance

• Current capability

• Insulation resistance

• Relevant electrical tests

Mechanical Performance

Depending on the applicable standard, consider:

• Tensile properties

• Elongation

• Flexibility

• Abrasion resistance

• Bending requirements

Environmental Performance

PV cable may be exposed to:

• UV radiation

• Heat

• Moisture

• Temperature cycling

• Chemical exposure

• Mechanical movement

The cable design must be suitable for the actual installation environment.

DOE PV cable-management guidance specifically highlights heat, UV exposure, chemical reactivity, moisture, abrasion, cable routing, bending, and support as factors affecting long-term DC-string cable reliability.

Why Solar Cable Color and Marking Matter

Cable color is often used to distinguish circuit polarity or identify different circuits, but project requirements may vary.

Buyers may specify:

• Red

• Black

• Other project-specific colors

Cable printing can also identify important information such as:

• Manufacturer

• Cable type

• Voltage rating

• Standard

• Conductor size

• Certification marking

• Production identification

Clear marking helps installers identify the correct cable and supports traceability.

The exact marking requirements should be checked against the applicable product standard and destination-market regulations.

How Should Solar Cable Be Packaged for Export?

Packaging becomes particularly important for international B2B orders.

Procurement specifications should define:

• Coil or reel length

• Drum dimensions

• Net weight

• Gross weight

• Label information

• Pallet requirements

• Moisture protection

• Container loading requirements

For long-distance export, the packaging should protect the cable against mechanical damage, moisture, contamination, and deformation.

For large projects, buyers may also request packaging designed for site handling and installation equipment.

What Should You Ask a Solar Cable Manufacturer Before Ordering?

Before placing a purchase order, ask the manufacturer for information on:

Product

• What conductor material is used?

• What insulation and sheath materials are used?

• What sizes are available?

• What voltage ratings are available?

• What temperature ratings are available?

Compliance

• Which standards does the cable meet?

• Is the product certified or tested for the target market?

• Can the manufacturer provide relevant test reports?

Manufacturing

• Where is the cable manufactured?

• What quality-control procedures are used?

• How is conductor resistance tested?

• How is finished-cable quality verified?

Customization

Can the supplier provide:

• Custom cable length

• Cable color

• Printing

• Packaging

• Conductor size

• Connector assembly

• OEM labeling

Delivery

Ask about:

• MOQ

• Production lead time

• Standard packing length

• Export packaging

• Shipment capability

• Production capacity for repeat orders

These questions allow buyers to compare suppliers using technical and operational criteria instead of comparing price alone.

Solar Cable Procurement Checklist

Before approving a supplier, use the following checklist.

Procurement Item	What to Verify
Cable type	PV wire / H1Z2Z2-K / IEC 62930 or project-specific designation
Conductor	Copper / tinned copper / aluminum
Size	mm² or AWG
Stranding	Conductor class and construction
Voltage	Rated DC voltage
Temperature	Continuous and applicable short-term ratings
Insulation	Material and thickness
Sheath	Material and environmental properties
Resistance	Manufacturer's specified DC resistance
Certification	Applicable market and standard
Test reports	Relevant product and certification evidence
Connector	Compatibility and ratings
Packaging	Coil / reel / drum configuration
Marking	Product identification and traceability
Customization	Color / printing / length / OEM
Quality control	Inspection and testing procedures
Lead time	Standard and bulk orders
Documentation	Datasheet / certificates / test reports

Solar Cable Procurement for OEM Projects

OEM projects require additional attention because the cable may become part of another company's product or PV assembly.

An OEM buyer may need:

• Specific conductor sizes

• Custom cable lengths

• Specific jacket colors

• Custom printing

• Packaging with private labels

• Connector configurations

• Assembly tolerances

• Batch traceability

• Inspection documentation

The supplier should be able to translate the buyer's technical specification into a controlled production specification.

This is where the difference between a simple trading supplier and a specialized solar cable manufacturer becomes important.

A manufacturer with direct control of conductor stranding, insulation extrusion, testing, printing, packaging, and final inspection can provide greater control over product consistency and customization.

Solar Cable Procurement for International Markets

International buyers should not assume that one cable specification is suitable for every country.

Different markets may require different:

• Product standards

• Certification systems

• Voltage ratings

• Fire-performance requirements

• Environmental requirements

• Connector systems

• Installation practices

UL Solutions notes that different global regulatory requirements determine which PV cables are appropriate for particular markets and provides testing and certification services against standards including EN 50618 and other PV cable requirements.

The procurement specification should therefore state the destination market before the supplier confirms the final cable construction.

How Much Does Solar Cable Cost?

Solar cable pricing depends on multiple variables.

The main cost drivers can include:

• Conductor material

• Copper price or aluminum price

• Cross-sectional area

• Insulation and sheath materials

• Voltage rating

• Certification requirements

• Cable length

• Connector assembly

• Packaging

• Order quantity

• Customization

• Shipping requirements

Copper conductor price is normally a major factor because copper represents a significant share of the cable's material cost.

For this reason, buyers should compare suppliers using a complete specification rather than comparing a price per meter without confirming construction and certification.

How to Compare Solar Cable Suppliers

A useful supplier comparison should include at least six dimensions:

Evaluation Area	Key Questions
Technical capability	Can the supplier manufacture the required construction?
Certification	Does the product meet the destination-market standard?
Quality control	How are raw materials and finished cables tested?
Manufacturing capacity	Can the supplier support the required volume?
Customization	Can it provide OEM specifications?
Documentation	Can it provide datasheets, test reports and traceability?

A low purchase price does not necessarily represent a lower total procurement cost if the cable has inconsistent dimensions, inadequate documentation, certification problems, poor packaging, or high failure rates.

Solar Cable Procurement: Manufacturer or Trading Company?

Both manufacturers and trading companies can participate in cable supply chains, but their capabilities may differ.

A manufacturer may have direct control over:

• Raw-material specifications

• Conductor production

• Insulation extrusion

• Cable testing

• Production scheduling

• OEM customization

• Quality records

A trading company may source products from one or more factories and manage commercial activities.

For large or recurring PV orders, buyers should understand who actually manufactures the cable, where the product is tested, and whose name appears on the certification and technical documentation.

This is particularly important when the project requires consistent specifications across multiple production batches.

Final Solar Cable Procurement Recommendations

A professional solar cable procurement process should start with the application, not with a cable size.

First determine:

What is the PV system voltage?

What current does the circuit carry?

How long is the cable run?

What voltage drop is acceptable?

What environmental conditions will the cable experience?

Which standard applies to the target market?

What certification and documentation are required?

Only after these questions are answered should the final cable specification be confirmed.

A complete procurement specification should normally define:

Conductor + size + construction + insulation + sheath + voltage rating + temperature rating + standard + certification + marking + packaging

Frequently Asked Questions

What should I check when buying solar cable?

Check conductor material and size, voltage rating, temperature rating, insulation and sheath construction, DC resistance, environmental performance, applicable standards, certification, connector compatibility, packaging, and supplier documentation.

What size solar cable should I buy?

The correct size depends on circuit current, operating voltage, cable length, allowable voltage drop, conductor material, temperature, installation conditions, and applicable ampacity requirements. Panel wattage alone is not enough to determine cable size.

What is the difference between PV cable and regular electrical cable?

PV cable is specifically designed and certified for photovoltaic applications and may need to withstand sunlight, outdoor exposure, temperature variation, moisture, and long-term DC operation.

What is H1Z2Z2-K solar cable?

H1Z2Z2-K is a photovoltaic cable designation associated with EN 50618 applications. Buyers should verify the manufacturer's actual certification, construction, voltage rating, and product documentation rather than relying on the designation alone.

What is UL 4703 PV wire?

UL 4703 is the UL standard for photovoltaic wire. UL Solutions lists photovoltaic wire under UL 4703 and provides testing and certification services for PV cable products.

What is IEC 62930 solar cable?

IEC 62930:2017 covers electric cables for photovoltaic systems with a rated DC voltage up to 1.5 kV. It applies to single-core cross-linked insulated cables with cross-linked sheath for the DC side of PV systems.

Should I buy 4 mm² or 6 mm² solar cable?

There is no universal answer. The correct size depends on the actual current, cable length, voltage drop, temperature, installation method, and applicable electrical requirements.

Can solar cable be customized?

Many manufacturers can customize cable length, conductor size, color, printing, packaging, and connector assemblies. The available options depend on the manufacturer's production capabilities and the required product standard.

What documents should a solar cable manufacturer provide?

Depending on the project, buyers may request a technical datasheet, applicable certificates, test reports, quality-management documentation, product markings, inspection records, and other traceability documents.

How do I choose a solar cable manufacturer?

Compare technical capability, certification, quality control, manufacturing capacity, customization capability, documentation, delivery capability, and product consistency rather than price alone.

Conclusion

Solar cable procurement is a technical sourcing process, not simply a price comparison exercise.

The correct cable must match the PV system's electrical requirements, environmental conditions, installation method, and destination-market standards.

A reliable procurement process should evaluate:

Specifications → Types → Sizing → Voltage Drop → Ampacity → Materials → Standards → Certification → Quality → Supplier Capability

IEC 62930 provides an international reference for PV cables up to 1.5 kV DC, while UL 4703 is a key North American standard for photovoltaic wire. EN 50618 is another important standard for European PV cable applications.

For buyers, the most important principle is simple:

Do not buy solar cable by size or price alone. Specify the complete cable construction and verify that the product, certification, testing, and supplier capabilities match the requirements of the PV project.

For a professional solar cable manufacturer such as FRCABLE, this procurement framework can also help international buyers evaluate standard PV cables, aluminum and copper conductor options, OEM cable specifications, customized printing and packaging, and market-specific certification requirements.