Full Interpretation of TÜV Rheinland Specification 2 PfG 2750/09.20

I. Bagninsic Definition & Standard Positioning

1. Standard Attribute

2 PfG 2750/09.20 is TÜV Rheinland proprietary test specification, not an official EU mandatory standard (EN / IEC)KBE Elektr....

• Foundation: Fully built on EN 50618:2014 (H1Z2Z2-K 1500V DC PV cable universal standard)

• Core upgrade: Adds exclusive long-term warm water hydrolysis aging test (AD8 grade submersion certification), the core threshold separating floating PV cables from ordinary rooftop PV1-F wires.

2. Target Product

Single-core 1500V DC photovoltaic cables specially developed for Floating PV (FPV / water-surface solar farms) (freshwater reservoirs, lakes, inland ponds).

3. Market Application Logic

• Ordinary rooftop, ground-mounted PV: Only EN 50618 certification is sufficient

• Floating / water-submerged PV projects: Global EPCs, owners and bidding documents universally require dual certification: EN 50618 + 2 PfG 2750/09.20

4. Clear Distinction from 2 PfG 2962/12.23

表格

Do not mix the two; saltwater projects cannot use cables only certified by 2 PfG 2750上海金友金....

II. Overall Test Logic of 2 PfG 2750

1. All test items of EN 50618 are fully inherited as basic inspection items

2. The biggest differentiation: Mandatory long-term warm water hydrolysis aging test (AD8 level), which EN 50618 does not enforce

3. EN 50618 only carries out short-term 60min water immersion withstand voltage test; 2 PfG 2750 forces continuous energized warm water aging for 100 days to simulate permanent underwater service.

III. Four Major Categories of Complete Test Items

Category 1: Structural, Conductor & Basic Electrical Tests (Identical to EN 50618)

1. Cable dimensional inspection: Outer diameter, insulation & sheath minimum thickness

2. Conductor performance:

   • Mandatory Class 5 multi-strand flexible copper; floating projects generally require tinned copper to prevent long-term water oxidation

   • Full cross-section tolerance & 20℃ DC resistance test; under-sized copper conductors will directly fail resistance inspection

3. Electrical performance:

   • Short-term water immersion AC withstand voltage (60min)

   • Insulation resistance test under normal temperature & humidity

Category 2: Mechanical & Thermal Aging of Materials (Identical to EN 50618)

1. Original mechanical property test: Tensile strength & elongation at break of insulation + sheath

2. Air thermal aging test: 135℃ × 168h, retain qualified tensile & elongation retention rate

3. Thermal deformation verification: Hot pressure test, hot elongation test (verify complete electron beam cross-linking of XLPO compound)

4. Low-temperature cold bending test: -40℃ winding & impact test, no cracking

Category 3. General Environmental Resistance Tests (Identical to EN 50618)

• UV climate aging test (simulate outdoor sunlight exposure)

• Ozone resistance test

• Flame retardant test IEC 60332-1 single cable vertical burn

• LSZH low-smoke zero-halogen performance test (Z characteristic)

Category 4: Exclusive Mandatory Test of 2 PfG 2750 (Not Required by EN 50618)

Long-Term Warm Water Hydrolysis Test (AD8 Grade Core Assessment)

Standard Test Conditions

• Medium: 50℃ constant temperature clean water

• Cycle: Continuous immersion for 100 days

• Loading: DC voltage applied to cable conductors during the whole soaking period

Post-Test Qualification Standards

1. Insulation & sheath tensile strength ≥7.0 N/mm²

2. Elongation at break ≥200%

3. Tensile strength & elongation change rate within standard allowable range

4. No visible defects: Delamination, bubbling, whitening, hydrolysis cracking

Material Threshold

Conventional general XLPE/XLPO PV cable compounds cannot pass the 100-day hydrolysis cycle. Only specially modified hydrolysis-resistant irradiated XLPO masterbatch meets the AD8 test requirements.

Optional Supplementary Tests (For Special Freshwater Floating Projects)

• Anti-mold & algae microbial erosion test

• Neutral salt fog aging test (transitional freshwater-coastal projects)

IV. Core Business Differentiation Guide for Engineering & Sales

1. EN 50618 (H1Z2Z2-K)

   Universal land-based photovoltaic cable standard; only short-term rain splash resistance, no long-term water immersion capability; forbidden for floating PV.

2. 2 PfG 2750/09.20 = EN 50618 full performance + 100-day 50℃ energized warm water hydrolysis (AD8 submersion grade)

   Applicable to all inland lake/reservoir floating PV power stations.

3. Drawing/Bidding Document Judgment Rule

   If both EN 50618 and 2 PfG 2750/09.20 are marked on client drawings, the project is confirmed as floating photovoltaic, and ordinary PV1-F cables cannot be substituted.

V. FAQ

Q1: What does AD8 grade correspond to in 2 PfG 2750 specification?

A: AD8 is the industry general name for the long-term submersion hydrolysis level defined by the 100-day 50℃ water immersion test in 2 PfG 2750, representing permanent underwater service qualification.

Q2: Can cables certified by 2 PfG 2750 be used for seaside salt fog floating projects?

A: Not recommended. Saltwater scenarios need to meet the stricter 2 PfG 2962/12.23 standard with additional salt fog & marine organism resistance tests.

Q3: Why must floating PV cables adopt tinned Class 5 copper conductors under this specification?

A: Long-term contact with water vapor will oxidize bare copper, increasing DC resistance and causing power loss; tin coating isolates water and oxygen to stabilize long-term electrical performance.

Q4: What failure risks will occur if ordinary EN50618 PV1-F replaces 2 PfG 2750 cable on floating power stations?

A: After 3–5 years of water immersion, insulation absorbs water and cracks, insulation resistance drops sharply, triggering inverter ground fault protection, frequent power limitation, and greatly shortened service life.

Hualan Technology was founded in 2020, is a collection of solar accessories production, sales, research and development and service as one of the high-tech enterprises. At present, the business covers the production and sales of solar photovoltaic cables, photovoltaic cable connectors.