ZA-NH-DJYP2V Fire-Resistant Screened Instrumentation Cable for Safety-Critical Signal Circuits

When a fire breaks out in a processing plant or tunnel, the first thing to fail is usually the signal cable. Not the PLC, not the actuator — the wire connecting them. Insulation melts, conductors short, and suddenly the emergency shutdown valve receives no command. The fire pump stays dead. The consequences range from extended downtime to total asset loss. The ZA-NH-DJYP2V is engineered to close that gap. Its mica-based fire barrier keeps low-voltage instrumentation loops intact under direct flame, while a copper tape screen rejects electromagnetic interference. The result is a single cable design that protects both circuit integrity during a fire and signal accuracy during normal operation. For procurement teams, that means fewer spare parts to stock and one less failure mode to worry about.

Signal Purity Under Electrical Noise

The overall copper tape screen, applied with a precise overlap, delivers 100% shielding coverage against radiated EMI. High-frequency drives, VFD motor cables, and adjacent power lines generate stray voltages that corrupt analog and digital signals. This screen drains that noise to ground. For your field instrumentation, that means stable 4-20 mA loops and error-free RS-485 communication. No ghost tripping of compressors, no corrupted transmitter data, and no hours lost chasing intermittent faults. Technicians trust what they see on the HMI. That keeps the plant online.

Circuit Integrity Line-to-Line for 180 Minutes

Each conductor is wrapped with a mica glass tape that, upon flame exposure, sinteres into an electrically resistant barrier. Even as polymer insulation chars, this layer prevents copper-to-copper contact. The cable continues to supply power and signal to critical devices — fire dampers, emergency lighting, remote I/O panels — while the enclosure is still engulfed. Compliance was verified to IEC 60331, sustaining over 180 minutes of circuit integrity. That window buys time for evacuations and automated suppression systems to work. It changes the cable from a liability into an active safety component.

Built to Contain Its Own Flame

The ZA classification means the cable body resists upward flame propagation under bundled conditions, tested to IEC 60332-3-22 Category A. The outer PVC sheath formulation restricts burning droplets and self-extinguishes once the external fire source is removed. In vertical cable trays spanning multiple floors, this property stops a localized fire from racing upward into secondary egress paths or HVAC risers. Your building’s containment strategy stays intact. Insurance underwriters recognize the difference, which can translate directly into lower premiums for the insured asset.

Site Handling Without Degrading Performance

The compound used for the inner sheath and insulation maintains flexibility at installation temperatures as low as -15 °C. Stranded copper conductors ease routing in cramped junction boxes and cable trays. At the same time, the cable resists standard industrial oils and moisture. Pulling it through a conduit doesn’t compromise the fire barrier, because the mica tape is mechanically reinforced. Commissioning teams spend less time on cable grooming and fault finding. That accelerated handover date puts the facility into revenue service sooner.

Technical Specifications

Industry Applications

• Oil & Gas Refineries — Sustains data links to motor-operated valves and emergency shutdown PLCs along open cable trays in fire-prone process units.
• Underground Metro & Road Tunnels — Maintains communication to jet fans, evacuation signage, and fire alarm loops during tunnel fires with high ambient temperatures.
• Power Generation & Substations — Prevents signal loss in grid protection relay circuits when a switchgear arc flash damages nearby control cables.
• Steel Mills & Foundries — Resists radiant heat and molten splash while carrying transducer signals from continuous casters and furnace zones.
• Data Centres — Protects room-to-room BMS and fire suppression trigger circuits, avoiding an early-phase cable failure that would disable the VESDA or gas suppression release.

International Compliance & QA Standards

• ✅ IEC 60332-3-22 — Test for vertical flame spread of bunched wires, Category A
• ✅ IEC 60331 — Circuit integrity under fire conditions for 180 minutes
• ✅ IEC 60228 — Conductors of insulated cables (Class 1, 2, 5)
• ✅ IEC 60304 — Standard colours for low-frequency cables and wires
• ✅ RoHS 3 (EU 2015/863) — Restriction of hazardous substances compliant
• ✅ ISO 9001:2015 — Manufacturing quality management system certified
• ✅ Factory Acceptance Test — Full continuity, insulation resistance, high-voltage spark test and dimensional check on every drum prior to shipment

FAQ

How do I confirm that ZA-NH-DJYP2V delivers full 180-minute circuit integrity in my specific installation?
Specify the test standard you require on your purchase order. Third-party type test certificates to IEC 60331 can be submitted with the bid. Keep the cable termination method compatible: ceramic terminal blocks or metal junction boxes that maintain physical separation during fire are mandatory. Without proper terminations, even a compliant cable will fail early.

What is the difference between the NH fire-resistance rating and simply using a flame-retardant cable?
A flame-retardant cable (e.g., ZA only) stops burning when the fire source is removed. It does not maintain voltage transmission during active combustion. NH-rated cable contains a mica tape that keeps the conductors electrically separate when exposed to 750–950 °C flame for a defined period. The NH function serves equipment that must run during a fire; the ZA function prevents the fire from travelling along the cable run. You need both for life-safety circuits.

Can you supply screened fire-resistant cables in paired or multi-pair configurations, and what are the typical lead times?
Yes. ZA-NH-DJYP2V can be manufactured as 1-pair, 2-pair, multi-pair, or multi-core with an overall screen. Lead time for standard configurations in catalogue cross-sections (0.75 mm² to 2.5 mm²) is typically 4-5 weeks ex-works. Custom colour codes, sequential metre marking on the sheath, and drum splitting to specific lengths add approximately 7 days. We also offer a low-smoke zero-halogen variant (ZA-NH-DJYP2V-R or similar) for enclosed public spaces; that version may require a longer raw-material procurement window.

Discuss Fire-Safety Cable Specifications for Your Next Project

Send us your instrument index, cable schedule, or a brief specification note. We will cross-reference it against IEC 60331 and your local installation code, then return a data sheet with the exact conductor screen, pair count, and sheath material your engineering team needs. Use the contact form or email cables@yourdomain.com to start the review.