Precision Meets Power: The ZXHL-200A Contact Resistance Tester for Modern HV Switchgear

Accurate measurement of contact resistance is a cornerstone of high-voltage (HV) switchgear maintenance and quality assurance. High resistance points, often hidden by surface oxidation or contamination, are precursors to overheating, arcing, and catastrophic failure. While traditional methods exist, the ZXHL-200A Contact Resistance Tester represents a significant technological leap, offering superior performance, reliability, and ease of use tailored for demanding power system environments.

Core Technology: Beyond the Pulse
The defining innovation of the ZXHL-200A lies in its high-frequency switching power supply combined with advanced digital circuitry. Unlike older generation pulsed-current testers that deliver a brief, high-current burst, the ZXHL-200A generates a continuous, stable DC test current (50A, 100A, 150A, or 200A). This continuous output is crucial:

1.Effective Oxide Breakdown: Sustained high current effectively punctures and breaks down resistive oxide layers and surface films on switch contacts, a common challenge especially with older or infrequently operated equipment. Pulsed testers often fail to achieve this penetration, leading to falsely low resistance readings that mask potential problems.

2.True Stable Measurement: Continuous current allows the measurement circuit to reach a true steady-state, providing a stable and representative value of the contact's resistance under significant load. Pulsed methods can suffer from measurement instability due to the transient nature of the current.

Key Advantages in the Field: A Comparative Lens

1.Unmatched Anti-Interference: Electrical substations are notoriously noisy environments. The ZXHL-200A's digital circuit design provides exceptional immunity. Even under strong electromagnetic interference, the displayed result (the last digit) exhibits remarkable stability, fluctuating by a maximum of ±1 digit. This ensures reliable readings are obtained consistently, right where they are needed most.

2.Enhanced Longevity & Reliability: The instrument is built for the long haul. The use of high-precision resistors minimizes the impact of temperature variations on measurement accuracy. Coupled with rugged military-grade connectors, the tester offers superior resistance to vibration and mechanical stress encountered during transportation and field use, reducing downtime and maintenance costs.

3.Field-Practical Design: Recognizing the needs of technicians, the ZXHL-200A prioritizes practicality. Its compact dimensions (380×350×260mm) and light weight (10kg, excluding accessories) make it significantly easier to transport and maneuver around switchyards and factories compared to older, bulkier alternatives.

Technical Specifications: Engineered for Accuracy

1.Measurement Range: 1 - 1999 µΩ (Ideal for HV switch contacts)

2.Resolution: 1 µΩ (Detects minute changes indicating wear or contamination)

3.Test Current: DC 50A, 100A, 150A, 200A (Selectable, Continuous Output)

4.Accuracy: ±0.5% (High precision for confident decision-making)

5.Display: 3½ digit LCD (Clear, stable readout)

6.Power Supply: AC 220V ±10%, 50Hz

7.Operating Environment: -10°C to 40°C, ≤80% RH (Suitable for most site conditions)

Conclusion: The Technician's Choice for Confidence
The ZXHL-200A Contact Resistance Tester moves beyond the limitations of traditional pulsed-current methods. Its core strength – continuous high-current output enabled by modern power supply technology – directly addresses the critical need to penetrate contact oxidation and obtain stable, true resistance values. Combined with exceptional anti-interference capabilities, robust construction, and user-friendly portability, it delivers reliable, high-precision measurements essential for:

1.Preventive Maintenance: Identifying deteriorating contacts before failure.

2.Acceptance Testing: Verifying contact integrity on new or refurbished HV switches.

3.Troubleshooting: Diagnosing overheating issues accurately.

For technicians and engineers responsible for the reliability of critical HV switching equipment, the ZXHL-200A provides a powerful, dependable, and practical tool that enhances both measurement accuracy and field efficiency.

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/