Faraday Cages for AC / PD High Voltage Testing: Industry Applications, Required Test Items & DEMIKS Power Custom Shielded Systems

Website: www.demikspower.com | Company: Shanghai DEMIKS Power Technology Co., Ltd.

Introduction – Why Faraday Cages Are Indispensable for Industrial AC & PD High Voltage Testing

Industrial Faraday cages (also named HV shielding rooms, PD test shielding enclosures) create a fully enclosed conductive shielding space to block external electromagnetic interference and contain internal high-voltage radiation. As a professional manufacturer of complete high voltage test equipment, Shanghai Demiks Power Technology Co., Ltd. designs customized large Faraday shielding rooms and compact desktop Faraday shielding boxes exclusively for AC & PD testing scenarios. Our full-range Faraday cage products solve high background noise pain points for power equipment factories, third-party HV test laboratories and global electrical importers. Visit our official site: www.demikspower.com for detailed technical parameters and customized shielding solutions.

Working Principle & Core Industry Value of DEMIKS High Voltage Faraday Cages

High voltage test shielding room for export certification, All DEMIKS Faraday cages adopt fully welded continuous conductive metal shell structures based on electrostatic shielding theory, delivering dual electromagnetic isolation for AC and PD testing:

1. Block External EMI to Guarantee Precise PD Measurement Our standard shielding system achieves shielding efficiency ≥65dB within the mainstream PD frequency band (0.5MHz–1.6MHz), controlling laboratory background noise stably below 3pC. This performance fully complies with IEC, ANSI and international type test requirements, eliminating signal drift caused by factory workshop interference during AC partial discharge testing.
2. Isolate Internal HV Electromagnetic Radiation & Improve Operation Safety High voltage boosting and partial discharge generate strong electromagnetic waves during testing. Our Faraday cage with multi-point low-resistance grounding system (ground resistance ≤0.3Ω) locks electric and magnetic fields inside the shielding enclosure, preventing EMI disturbance to factory CNC equipment, PLC control systems and precision measuring instruments. The fully grounded metal structure also isolates live high voltage electric fields to avoid induction electric shock hazards for operators.
3. Standardized Test Environment for Global Export Certification Overseas buyers of transformers, XLPE power cables and switch-gears require AC & PD test reports obtained inside qualified Faraday cages for CE, UL and third-party certification audits. Every DEMIKS Faraday cage comes with official third-party shielding efficiency test certificates, directly supporting export inspection and cross-border order delivery for global importers.

All Mandatory High Voltage Tests That Require Faraday Cage Shielding

AC withstand voltage PD joint test, transformer partial discharge test shielding room, CT PT PD test Faraday box, XLPE cable resonant PD test chamber, RIV test shielding enclosure All tests below cannot obtain qualified, repeatable test data without a dedicated Faraday cage shielding environment.

Core Test 1 – Combined AC Withstand Voltage & Partial Discharge Test (Most Widely Used)

1. Oil-immersed & Dry Type Transformer PD Testing For 10kV–220kV distribution and power transformers, technicians apply 1.5 times rated AC voltage and monitor partial discharge magnitude to detect winding insulation bubbles, delamination and damp defects. High background noise without Faraday shielding will hide minor insulation flaws and cause unqualified products to flow to the market.
2. Current Transformer (CT) & Voltage Transformer (PT) PD Inspection Miniature instrument transformers feature ultra-fine insulation layers and extremely weak PD signals, demanding strict low-noise testing conditions. DEMIKS desktop Faraday shielding boxes support mass batch sampling for CT/PT manufacturers.
3. XLPE Power Cable & Cable Accessory Resonant AC PD Test Our large customized Faraday shielding rooms can accommodate complete cable reels up to dozens of meters long, eliminating signal fluctuation during variable frequency resonant withstand voltage and PD synchronous testing for 1kV–220kV power cables, cable terminals and intermediate joints.
4. Zinc Oxide Surge Arrester & HV Bushing PD Detection The shielding chamber accurately identifies internal air-gap discharge defects inside arrester cores, porcelain bushings and composite high voltage sleeves.
5. High & Medium Voltage Switch-gear, GIS Gas Insulated Cabinet PD Type Test Detect discharge defects on busbars, contact components and insulating partitions of ring main units and GIS equipment.

Secondary HV Tests Requiring Faraday Cage Shielding

1. Dielectric Loss (tanδ) Test: Cut stray capacitance interference to upgrade measurement accuracy
2. Radio Interference Voltage (RIV) Test: Faraday shielding chamber is a mandatory standard test environment
3. Lightning Impulse & Switching Impulse Voltage Test: Block strong electromagnetic pulses to protect PD measuring instruments
4. Power Capacitor & Reactor AC Withstand & PD Sampling Test

DEMIKS Full Range of Custom Faraday Cage Products for AC / PD Testing

DMX-PBS large HV shielding room, DMX-PBX desktop Faraday shielding box, custom Faraday cage for high voltage lab, Faraday cage matching resonant test system Shanghai DEMIKS Power Technology Company develops two core Faraday cage product lines, compatible with our self-developed variable frequency resonant test sets, multi-channel PD detectors and AC high voltage boosting systems. Customers can purchase shielding enclosures separately or order a complete integrated HV test solution. All product technical data-sheets are downloadable on our official website www.demikspower.com.

DMX-PBS Series Large Integrated High Voltage Faraday Shielding Room

Target customers: Transformer factories, cable manufacturers, official HV test laboratories, third-party certification institutes

1. Structural Configuration 2.0–2.5mm cold-rolled steel full-welded six-sided shielding shell; double-layer shielding optional; equipped with airtight electric shielding main door (for large transformers & cable reel access), personnel shielding wicket, wave-guide ventilation windows, dedicated power line filters, indoor copper grounding bars, explosion-proof shielded lighting and isolated control shielding compartment. All wiring inlets adopt filtering treatment to eliminate electromagnetic leakage gaps.
2. Key Technical Specifications

• Shielding efficiency: ≥65dB @ 0.5MHz ~ 1.6MHz PD frequency band
• Stable background noise: ≤3pC
• Independent composite grounding grid, grounding resistance ≤0.3Ω
• Fully customized dimensions: from 6m×4m×3m to 25m×15m×14m
• Compliance standards: GB/T 12190, IEC 60270, ANSI C37 series
• Unique Supporting Advantages Perfect linkage with DEMIKSself-produced variable frequency resonant test equipment, multi-channel partial discharge detectors and AC high voltage systems. Complete factory joint debugging before delivery; customers only need basic civil engineering for on-site installation. We provide door-to-door installation, shielding efficiency re-inspection and full operator training services.

 DMX-PBX Series Desktop Mini Faraday Shielding Box

Target customers: Instrument transformer, surge arrester and HV bushing mass production lines, overseas small-batch export sampling inspection

1. Product Features Integrated copper mesh & aluminum plate sealed cabinet with independent grounding terminals and filtered power sockets. Compact size for bench placement and single-person operation. Ideal for small electrical component batch PD testing with lower investment cost compared with large shielding rooms.
2. Technical Indicators Background noise ≤5pC, shielding efficiency ≥60dB; multiple standard sizes from 0.4m×0.4m×0.4m to 1.2m×1m×1m; custom internal insulation support frames available upon request.

Value-Added Supporting Services from DEMIKS Power

1. Existing HV lab shielding renovation: Gap sealing, filter installation and grounding system upgrade for old un-shielded test workshops to save customer reconstruction cost.
2. Complete export packaged solutions: Faraday shielding room + PD detector + AC withstand test equipment integrated export, with multilingual English/Italian technical manuals and third-party test reports to meet certification demands for European, Southeast Asian and Middle Eastern importers
3. Lifetime remote technical support: Remote troubleshooting for shielding efficiency failure and excessive background noise, permanent spare parts supply

Common Testing Defects Without Qualified Faraday Cage for AC & PD Test

1. Continuous drifting PD readings and high background noise, leading to misjudgment of qualified power equipment or outflow of defective insulated products
2. Overseas third-party labs refuse to recognize PD & AC test data obtained without standard Faraday shielding, causing cross-border order delivery delays
3. Internal high voltage electromagnetic leakage disturbs factory CNC machines, PLC and precision measuring equipment, triggering production line shutdown
4. Uninsulated high voltage electric fields bring safety risks including operator induction electric shock and electric burns

Core Competitive Advantages of Shanghai DEMIKS Power Faraday Cage Systems

Shanghai high voltage Faraday cage manufacturer, custom PD test shielding room supplier, complete AC PD test equipment solution provider (demikspower.com)

1. Specialized in power HV test scenarios: Our shielding schemes are optimized for transformers, cables and instrument transformers AC/PD test working conditions, not general-purpose electromagnetic shielding rooms
2. Native matching with self-developed HV test instruments: Faraday shielding systems cooperate seamlessly with DEMIKS PD detectors and resonant boosting devices, delivering industry-leading low background noise performance
3. Global multi-scene customization support: English, Italian and Chinese technical documentation for European importers including Rome-based electrical traders, Southeast Asian and Middle Eastern power manufacturers
4. In-house professional construction team: Nationwide on-site installation and commissioning, issuing official shielding efficiency inspection reports after project completion to satisfy both domestic type test and overseas export certification requirements

Conclusion – Faraday Cage Is Standard Mandatory Infrastructure for AC & PD High Voltage Testing

Against the backdrop of stricter global power equipment quality control standards, Faraday cages are no longer optional auxiliary equipment but essential infrastructure for AC withstand voltage and Partial Discharge testing. DMX series Faraday shielding systems manufactured by Shanghai DEMIKS Power Technology provide standardized, fully compliant low-interference test environments for domestic and international power equipment manufacturers and test labs. Our integrated HV shielding solutions help Chinese high voltage electrical products pass global IEC, ANSI and CE certification smoothly and expand overseas export markets.

For detailed Faraday cage technical catalogs, quotation data and customized on-site layout schemes, visit our official website www.demikspower.com and consult our professional HV test technical engineers online anytime.

Take XLPE Cable HV Testing Lab as an example to show you how to select the suitable Faraday Cage. 

Notes：

1.  Above are standard recommended dimensions, custom sizing available based on site conditions and test equipment layout.
2. Control rooms are located inside the HV hall as independent shielded structures, with shielded observation window and signal filter channels.
3. All specifications comply with IEC 60270 & GB/T 12190 standards, background noise ≤3–5 pC.
4.  Full turnkey solution available: variable frequency resonant test system, multi-channel PD detector, AC withstand voltage equipment.

Pre-Order Specification Questions of Faraday Cage

Basic Lab & Construction Layout Questions

1. What are the exact internal dimensions required for your high voltage PD test Faraday cage laboratory?
2. What size shielding door do you need for moving transformers, cable reels and HV test equipment into the Faraday cage room?
3. What dimension do you plan for the independent control room attached to your AC/PD test shielding chamber?
4. Will this PD test Faraday cage be constructed inside a brand-new building or an existing renovated workshop?
5. Can you provide full architectural blueprints of the building where the high voltage shielding room will be installed?
6. Will the Faraday cage shielding system strictly follow your customized structural design specifications?
7. Could you clarify the full construction scope and detailed technical construction standards for the HV Faraday cage project?
8. Where will you locate the operator control room relative to the main Faraday shielding chamber? Where will the dedicated low-resistance grounding grid be placed?

Equipment & Lifting System Requirements

1. What overhead crane tonnage capacity is required inside your PD test Faraday cage laboratory for handling heavy power equipment test samples?

Ventilation, Lighting & Auxiliary System Demands

1. What design solutions do you require for fresh air supply, explosion-proof shielded lighting and wave-guide ventilation systems inside the HV shielding room?
2. Could you provide a detailed layout drawing of all your AC withstand & partial discharge test equipment to be placed inside the Faraday cage lab?

Building Load, Fire Safety & Thermal Insulation Specs

1. What roof load-bearing capacity standard must the building meet to support the full Faraday cage shielding structure and internal test machinery?
2. Are there special local fire protection and workplace safety compliance requirements for your high voltage test shielding laboratory?
3. What thermal insulation treatment standards do you require for the Faraday cage enclosure? Will we follow your custom insulation design or our standard factory solution?

Shanghai Demiks Power Company provide custom Faraday cage solutions (www.demikspower.com). Welcome to inquiry us. Thank you!