ZA-DJVPVP Shielded Instrumentation Cable – Reliable Signal Transmission in High-EMI Industrial Environments
Keeping a signal clean in a plant floor dense with VFDs, motor starters, and high-voltage power trays isn’t a feature. It’s the bare minimum your control system demands. Signal distortion and unplanned downtime eat into project margins fast. The ZA-DJVPVP cable is engineered to prevent exactly that — delivering consistent, low-noise transmission through a double-shielded construction that meets flame-retardant Class A requirements. It reduces the troubleshooting hours your field engineers spend chasing ghost signals and keeps your automation layer stable.
Construction That Blocks Noise Before It Reaches Your PLC
Every layer in this cable works to contain interference and maintain signal integrity across long trunking runs. No magic. Just predictable electro-mechanical behaviour built into a robust physical design.
Dual shielding: individual pair foil tape + overall tinned copper wire braid
Noise current couples onto a shield and must find a low-impedance path to ground. The aluminium/polyester tape wrapped around each twisted pair blocks electrostatic pick-up at the source, while the high-coverage tinned copper braid provides a low-resistance drain path for low-frequency magnetic fields. This combination keeps near-end crosstalk low and protects adjacent circuits in the same tray. Your SCADA loop reads clean values; your maintenance team stops chasing intermittent faults.
Flame-retardant Class A (ZA-grade) PVC compound
Cable fires in vertical risers or congested cable trays are a compliance non-negotiable. The sheath and insulation use a compound tested to limit flame propagation across a bundle. This means the cable meets the layout restrictions for installation in industrial plants and high-rise building services without requiring additional fireproofing wraps. Less material, fewer labour hours, and a straightforward approval path with the insurer and local AHJ.
Solid or stranded bare copper conductors, precision-twisted pairs
Pair-to-pair twist lay variation minimises differential mode interference. Standard conductor sizing from 0.5 mm² to 2.5 mm² supports both long-loop 4–20 mA instruments and digital RS-485 networks without pushing voltage drop beyond acceptable limits at the far end of the segment.
Rugged PVC inner sheath under the outer braid
A separating layer between the pair screens and the overall braid prevents mechanical abrasion during pulling and reduces the risk of screen shorting at termination gland points. This adds a fraction of millimetres to the overall diameter but cuts field termination rework by a measurable margin — especially on retrofit projects where cables are pulled through existing crowded trays.
Technical Specifications & Dimensions
Specifications listed below reflect the standard production configuration. Custom conductor sizes, sheath materials (LSZH, PE), and armour options are available against project datasheets.
| Parameter | Standard Value / Range |
|---|---|
| Cable type | Multi-pair shielded instrumentation cable |
| Model designation | ZA-DJVPVP (Individual + overall screen) |
| Conductor material | Annealed bare copper, Class 1 or Class 2 |
| Conductor size range | 0.5 mm² – 2.5 mm² (typical: 1.0 mm² and 1.5 mm² for field instruments) |
| Pair count | 1 pair to 24 pairs (other counts on request) |
| Insulation | PVC (ZA flame-retardant compound) |
| Individual pair screen | Aluminium/polyester tape, 100% coverage, in contact with drain wire |
| Overall screen | Tinned copper wire braid, coverage ≥ 85% |
| Inner sheath | PVC bedding compound |
| Outer sheath | PVC (ZA flame-retardant compound), black or blue |
| Rated voltage U₀/U | 300/500 V |
| Temperature range, fixed installation | -20 °C to +70 °C |
| Bending radius, fixed | 8 × overall diameter |
| Flame retardance | IEC 60332-3-22 (Category A), GB/T 18380.33 |
| Applicable standards | GB/T 19666 (flame retardance), JB/T 13486 (computer & instrumentation cable), capable of being tested to IEC 60332-1, IEC 61034, IEC 60754 when agreed in purchase order |
Where This Cable Fits Into Real Projects
Industrial procurement usually starts with a line on a cable schedule, not a catalogue. Here are the contexts where we see sustained demand for ZA-DJVPVP.
- Process plant DCS and PLC interconnections – Connects remote I/O panels to transmitters, solenoid valves, and flow meters in chemical and pharmaceutical facilities where signal accuracy directly affects batch consistency.
- Power generation and distribution substations – Links CT/VT secondary circuits and RTU serial links across switchgear bays. The double shield handles the intense electric field environment near busbars and disconnect switches.
- Tunnel and mass transit ventilation control – Monitors air quality sensors and damper position feedback loops. Flame-retardant Class A properties support approval for long uninterrupted runs through tunnel service channels.
- Water and wastewater treatment SCADA – Carries analogue level and flow signals across plant sections. Moisture resistance of the PVC layers and stable capacitance per metre prevent zero-point drift that prompts recalibration.
- Manufacturing automation and CNC machinery data lines – Moves encoder feedback and sensor data along cable chains and within control cabinets. Tight pair twist and metallic shielding let it sit in the same tray as unshielded power cables without data loss.
International Compliance & Quality Assurance
- ✅ IEC 60332-3-22 – Flame propagation test for bunched cables, Category A
- ✅ GB/T 18380.33 – Equivalent to IEC 60332-3-22, mandated for ZA-grade cables
- ✅ JB/T 13486 – Computer and instrumentation cable construction requirements
- ✅ CE marking available under the Low Voltage Directive (LVD 2014/35/EU) when ordered with harmonised test documentation
- ✅ RoHS (2011/65/EU) compliant – PVC formulations free of restricted phthalates and heavy metals
- ✅ ISO 9001:2015 certified manufacturing process with full batch traceability
FAQ
What does the “ZA” prefix actually mean for installation rules?
ZA denotes flame-retardant Class A per GB/T 19666, tested on vertical bunched cable samples. In practice this allows tighter grouping and vertical riser installation in industrial environments where local fire codes restrict standard PVC cables. For export projects, we map the flame performance to IEC 60332-3-22 Cat A. If you need additional low-smoke or zero-halogen properties, the cable can be re-engineered with LSZH compounds under request.
How does the DJVPVP shielding compare against SWB (steel wire braid) for instrumentation?
Steel wire braid provides mechanical protection and some magnetic shielding but adds weight and bending stiffness. The aluminium-tape-plus-copper-braid structure of DJVPVP is designed for electrical noise rejection first: the foil handles high-frequency impedance, the copper braid covers low-frequency and provides a low-resistance ground path. If you need armour against crushing, we can add a galvanised steel wire armour layer to the exact same core assembly.
Can you supply long continuous lengths for pulling through cable ducts without intermediate joints?
Yes. Standard drum lengths reach 1,000 m per piece for most pair counts, and we can supply up to 2,000 m by arrangement. All factory splices are avoided on continuous lengths. We also provide pulling-head measurements and drum labelling that matches your cable schedule line items to simplify incoming inspection and material handling on site.
Request a datasheet or a project-specific sample
Send us your cable schedule excerpt, signal type, and installation layout. We will return a full electrical and dimensional datasheet, a section drawing, and a delivery lead time within one business day. Contact our engineering desk at [email/contact link] or use the inquiry form on this page.