Rated Voltage 1.8/3kV Cross‑linked Polyethylene Insulated (Flame‑retardant, Fire‑resistant) Power Cable

Usage Characteristics and Technical Parameters

- Rated Operating Voltage (U0/U): 0.6/1 kV and 1.8/3 kV.
- Maximum System Voltage (Um): 3.6 kV.
- Max long-term conductor working temperature: 90°C.
- Max short-circuit conductor temperature (<= 5s): <= 250°C (original insulation performance maintained after short circuit).
- Laying temperature: >= 0°C.
- Minimum Bending Radius:
  - Single-core unarmored: >= 20D (D = outer diameter).
  - Multi-core unarmored: >= 15D.
  - Armored: >= 12D.
- Partial discharge test (factory test): < 20pC at rated voltage U0 <= 18kV.

Product Structure

From conductor to outer sheath:
- Conductor: Class 1 (solid) or Class 2 (stranded) copper or aluminum alloy per GB/T 3956; good conductivity and mechanical strength.
- Insulation: XLPE — thermoset; long-term operating temperature 90°C (vs 70°C for PVC). Nominal thickness for 1.8/3kV: uniformly 2.0mm.
- Flame-retardant / Fire-resistant Structure: Flame-retardant achieved through insulation and sheath compound formulas; fire-resistant achieved by wrapping mica tape over conductor to ensure circuit integrity.
- Filling and wrapping: Flame-retardant filler; wrapped to ensure round shape.
- Armoring (optional): Steel tape (code "2", e.g., YJV22) or steel wire; enhanced mechanical protection.
- Outer Sheath: Flame-retardant PVC or LSZH polyolefin.

Flame-retardant and Fire-resistant Performance

Flame-retardant Performance (ZR): Per GB/T 19666-2019, grades ZA (Class A), ZB (Class B), ZC (Class C):

Fire-resistant Performance (NH): Per GB/T 19216.1-2021:
- Fire temperature: 830°C to 950°C; continuous power supply for >= 90 minutes; line maintains integrity without disconnection.

Additional Property — Halogen-free Low-smoke (WDZ): Sheath uses LSZH polyolefin. During combustion, releases extremely low halogen acid gases (no halogen), extremely low smoke (low smoke), with far lower toxicity and corrosivity than standard PVC. Especially suitable for densely populated and precision equipment locations.

Model Codes and Naming

- Z: Single-grade flame-retardant (ZC class; replaces old ZR).
- ZA/ZB/ZC: Flame-retardant Class A/B/C.
- N: Fire-resistant cable.
- WDZ: Halogen-free low-smoke flame-retardant.
- YJ: XLPE insulation.
- V: PVC sheath; Y: PE sheath; E: LSZH polyolefin sheath.
- 22: Steel tape armored PVC sheath; 32/33: Steel wire armored PVC/PE sheath.

Typical Model Examples:

Conductor Cross-sections and Insulation Thickness

Cross-section range for 1.8/3kV: typically 2.5 to 630 mm². Insulation thickness per GB/T 12706.1-2020: uniformly 2.0mm (maintained at 2.0mm even for cross-sections >= 50mm²).
- Single-core: up to 630 mm².
- Multi-core (2, 3, 4, 5-core and 3+1/3+2/4+1): up to 400 mm².

VApplication Areas

- Power distribution systems: 1.8/3kV power lines for power transmission.
- High fire-safety locations: Flame-retardant and fire-resistant cables for demanding fire safety conditions; LSZH types especially for densely populated public areas.
- Emergency system distribution: Fire alarm, firefighting equipment, emergency疏散 systems.
- Metallurgy, power, petrochemical, and urban power grid construction.
- Nuclear plants, underground facilities, tunnels, high-rise buildings, radio/TV stations (LSZH type).

Selection Guide and Notes

1. Flame-retardant grade: Grade ZA or ZB recommended for single-specification bundled installation; Grade ZA for dense multi-specification bundled installation. Grade ZC for basic flame-retardant requirements.
2. Fire-resistant cables (N): Per GB/T 19216.1-2021 (830°C with shock and vibration, 90min circuit integrity); can be combined with flame-retardant as ZAN, ZBN, ZCN.
3. Halogen-free low-smoke: Use WDZN-type in densely populated public areas and precision electronics rooms to minimize toxic smoke secondary damage.
4. Armoring: Armored type (e.g., YJV22) for direct burial or locations with mechanical forces; unarmored type for cable trays and indoor installations without mechanical damage risk.

Packaging and Storage

- Packaging: Cables to be delivered coiled on cable drums.
- Storage: Store in ventilated, dry, and corrosion-free warehouse.
- Storage Temperature: Not lower than 0°C.