N-DJYPVP Fire-Resistant Shielded Instrumentation Cable
A signal lost mid-fire can disable an emergency shutdown. That silence risks assets and lives. The N-DJYPVP cable keeps those circuits alive. Its mica tape fire barrier holds integrity through a 750°C flame, buying operators the minutes needed to evacuate, vent, and isolate—while the dual-layer copper braid screen blocks the electromagnetic noise that corrupts low-voltage instrument loops in heavy industrial plants.
Fire Integrity Under Direct Flame
Most standard cables fail within seconds of fire exposure. N-DJYPVP wraps each conductor in a mica-glass tape, then covers the core assembly with an additional fire barrier where required. This design maintains circuit continuity for 90 minutes at 750°C under IEC 60331 test conditions. Emergency shutdown valves, pressurised alarm systems, and smoke extraction fans keep functioning exactly when they are needed. Downtime turns into managed shutdown.
Dual-Layer Shielding for High-EMI Environments
Individual twisted pairs carry a tinned copper braid screen. A second overall braid wraps the entire bundle. Two separate conductive envelopes achieve near-total rejection of stray magnetic and electric fields. Clean signals mean fewer PLC misreads and no nuisance trips on variable frequency drive circuits. The cost of one false trip often exceeds the cable budget for an entire loop.
XLPE Insulation That Outperforms Standard PVC
Cross-linked polyethylene holds its dielectric strength at conductor temperatures that soften ordinary PVC. Lower dielectric constant and stable capacitance over distance let you pull longer home runs without signal repeaters. For sprawling process plants or multi-level conveyor networks, that slashes junction-box count and commissioning hours.
Flame-Retardant Sheath with Low Acid Gas Emission
The outer PVC compound is formulated to resist vertical flame propagation and self-extinguish after the ignition source is removed. During combustion, acid gas generation stays below the thresholds that corrode switchgear contacts and control-room electronics. Secondary damage costs get capped before the fire is even out.
Colour-Coded Cores That Speed Termination
Every twisted pair carries a unique number and a distinct base/stripe colour combination, printed clearly on the insulation. Termination errors drop sharply because the identification survives pulling lubricant and cable gland friction. On a panel with 400 terminations, that alone pays for the spec upgrade.
Technical Specifications & Dimensions
Parameters confirmed at factory before dispatch. Each value is a typical benchmark; customer-specific builds can tighten tolerances further.
| Parameter | Specification |
|---|---|
| Conductor Material | Stranded annealed bare copper (tinned on request) |
| Conductor Class | IEC 60228 Class 2 or Class 5 flexible |
| Fire Barrier | Phlogopite mica tape with glass-fibre carrier |
| Insulation | Cross-linked polyethylene (XLPE) |
| Pair Shielding | Tinned copper braid, nominal coverage ≥ 80% |
| Overall Shielding | Tinned copper braid, nominal coverage ≥ 85% |
| Outer Sheath | Flame-retardant PVC, black or grey (LSZH sheath optional) |
| Rated Voltage U₀/U | 300 / 500 V |
| Test Voltage | 2000 V for 5 minutes |
| Temperature Range | -15°C to +70°C (fixed); XLPE conductor max 90°C |
| Minimum Bending Radius | 12× outer diameter for general installation |
| Core Cross-Sections | 0.5 mm², 0.75 mm², 1.0 mm², 1.5 mm², 2.5 mm² |
| Pair Count | 1 to 24 pairs as standard; larger counts on request |
| Fire Integrity Standard | IEC 60331-21 (90 min at 750°C with mechanical shock) |
| Flame Retardance | IEC 60332-1-2; IEC 60332-3-24 (Cat C) |
| Smoke Density | IEC 61034-2, light transmittance ≥ 60% |
| Acid Gas Emission | IEC 60754-2, pH ≥ 4.3, conductivity ≤ 10 µS/mm |
Industry Applications & Scenario Validation
- Oil & Gas processing trains: Sustains signal to motor-operated valves and gas detectors during flash fires, buying critical isolation time.
- Power generation and T&D substations: Provides noise-immune links between CT/VT metering circuits and protective relays in high magnetic-field zones.
- Tunnel and metro ventilation control: Keeps jet fans and damper actuators online when ambient temperature spikes above 250°C.
- Steel mills and casting shops: Withstands nearby induction furnaces without bit errors on load-cell and thermocouple extension loops.
- Pharmaceutical cleanrooms: Low-smoke, low-toxicity performance protects high-investment batch integrity even under a fire scenario.
International Compliance & QA Standards
Each production lot ships with a mill test report. Third-party witness testing available on request.
- ✅ IEC 60331-21 — Circuit integrity under fire at 750°C
- ✅ IEC 60332-1-2 / IEC 60332-3-24 — Flame propagation resistance
- ✅ IEC 61034-2 — Smoke density measurement
- ✅ IEC 60754-2 — Halogen acid gas content
- ✅ EN 50200 — Fire resistance for emergency circuits
- ✅ CE Marking under the Low Voltage Directive 2014/35/EU
- ✅ RoHS Directive 2011/65/EU compliant
- ✅ ISO 9001:2015 certified manufacturing and testing
FAQ
What separates N-DJYPVP from a standard DJYPVP instrumentation cable?
A layer of mica-glass tape is applied over each conductor. During a fire, the mica forms a cohesive ceramic-like barrier that prevents conductor-to-conductor shorting. Standard DJYPVP provides excellent shielding but will fail rapidly when directly exposed to flame. N-DJYPVP is built to maintain defined circuit integrity for a minimum of 90 minutes at 750°C, which makes it suitable for emergency shutdown loops and active fire-safety systems.
Can the outer sheath be switched to LSZH (Low Smoke Zero Halogen)?
Yes. We supply N-DJYPVP with a thermoset LSZH compound that meets IEC 60754 and IEC 61034 requirements. Transmittance values remain above 80% during smoke-density tests. This configuration is often specified for underground transit systems, data centres, and enclosed public spaces where acidic smoke would cause secondary equipment damage.
What is the typical lead time for custom pair counts and color-coding?
For regular stock configurations up to 12 pairs, ex-works dispatch is usually within 10–14 working days. Larger pair counts, custom jacket colours, or non-standard conductor strands add approximately one week. Full drums with sequential meter marking and pre-cut lengths can be arranged. We recommend locking the cable schedule early during the detailed engineering phase to secure production slots.
Get a Quote and Factory Test Report
Specify your required pair count, cross-section, sheath material, and any reference international standard. We return a datasheet, a delivery schedule, and a per-metre or per-drum quote—normally within the same working day. Reach our technical desk at [email] or request a callback.