ZX-Q15: Integrated HV Testing & Fault Location for Cable Networks

For technicians battling elusive high-resistance faults (HRF) in power cables, the ZX-Q15 Cable High Resistance Fault Location Bridge Tester presents a compelling, multi-functional solution. Combining DC withstand voltage testing, fault burn-down, and precise bridge-based pre-location into a single, portable unit (≤12kg), it addresses key challenges faced by field teams.

Core Functionality & Design:
At its heart, the ZX-Q15 employs a switching power supply generating a 0-15kV DC negative high-voltage constant current source. This HV source and a precision balanced bridge circuit (utilizing a proportional potentiometer, high-sensitivity amplifier, and galvanometer) are housed together at high potential within a rugged industrial plastic chassis. Ingeniously, operator controls remain at ground potential, accessed safely via an insulating rod. Test connections use specialized double-core HV rubber cable, and critical resistance measurements leverage a four-terminal (Kelvin) method, eliminating errors from lead resistance – a significant advantage for accuracy.

Three Key Capabilities in One Unit:

1.DC Withstand Voltage Testing (0-15kV, 30mA max): Perform routine dielectric strength checks or diagnostic testing on cables.

2.Fault Burn-Down (0-15kV, 30mA max): "Burn" through high-resistance or flashover fault points, effectively lowering their resistance to a level detectable by other methods or this bridge itself.

3.Bridge-Based Fault Pre-Location: The core strength. Using the balanced Wheatstone bridge principle and four-terminal measurement, it provides a distance-to-fault (D) reading with high accuracy: ±(0.2%·L ±1) meters, where L is the total cable length. This delivers a crucial, reliable pre-location estimate.

ZX-Q15 vs. Traditional TDR: Finding the Right Tool
While Time Domain Reflectometry (TDR) locators dominate low-resistance fault and open-circuit finding, the ZX-Q15 carves out a vital niche, particularly for HRFs:

1.Superior for High Resistance: TDR struggles with high-impedance faults where the reflection coefficient is very small. The ZX-Q15 bridge method excels precisely in this regime, especially after burn-down.

2.Cost-Effectiveness: A full TDR/Acoustic/Earth Gradient location suite represents a significant investment. The ZX-Q15 offers a substantially lower entry price.

3.Simplicity & Ease of Use: Operating the bridge requires less specialized waveform interpretation expertise than advanced TDR units. Its integrated burn-down capability streamlines the process for HRFs.

4.Complementary, Not Replacement: Professional teams often use the ZX-Q15 alongside TDR. The Q15 quickly pre-locates the HRF area (especially post-burn), then TDR or acoustic methods provide precise pinpointing. This hybrid approach is faster and more reliable than TDR alone on tough HRFs.

Ideal User Profiles:

1.Professional Repair Teams (Utilities, Large Industrials): Appreciate its speed in HRF pre-location, robust burn-down capability, and role as a powerful complement to TDR/acoustic pinpointing gear. Reduces outage duration.

2.Smaller Utilities & Industrial Plants: With limited cable inventory, shorter runs, and infrequent complex faults, the ZX-Q15 offers a highly capable, cost-effective "all-in-one" solution for withstand testing, burn-down, and pre-location, eliminating the need for expensive, complex TDR systems.

3.Cable Manufacturers: Ideal for factory testing to locate breakdown points during production or QA. Its portability enables on-site location services for customers. (Optional digital capacitance meter aids break finding).

Technical Specifications Summary:

1.HV Output: 0-15kV DC (Negative), Continuously Adjustable

2.Max Current: 30mA (Test & Burn)

3.Pre-location Accuracy: ±(0.2%·L ±1) meters

4.Power Supply: AC 220V ±10%

5.Anti-Interference: > 100V AC

6.Weight: ≤12 kg

7.Dimensions: 450 x 330 x 320 mm

Conclusion:
The ZX-Q15 Bridge Tester stands out for its practical integration of high-voltage generation, fault conditioning (burn-down), and highly accurate bridge-based pre-location specifically optimized for challenging high-resistance cable faults. Its portability, operator safety design (insulating rod operation), and elimination of lead resistance errors via four-terminal measurement make it a robust field tool. While TDR excels in other fault types, the ZX-Q15 remains the preferred or essential tool for efficient HRF resolution, particularly valued by smaller operators for its affordability and by large teams as a critical component in a comprehensive fault location strategy. Its ability to simplify and accelerate the initial stages of HRF location translates directly into reduced downtime and operational cost savings.

GDZX is a manufacturer of power detection equipment, offering a diverse range of products with comprehensive models and providing professional technical support. Contact us at +86-27-6552607 or +86-17396104357.Website: http://en.gdzxdl.com/