Research on Application of Leakage Tracking Test Apparatus in Evaluation of Tracking Resistance Performance of Insulating Materials

Abstract
Against the backdrop of the rapid development of electronic and electrical appliances, electrical equipment and new energy industries, solid insulating materials are prone to surface leakage current induced by dust, moisture, salt fog and other pollutants under long-term humid and polluted service conditions, which will further cause tracking corrosion, insulation breakdown and even electrical fire accidents. As a high-precision testing equipment specially developed to evaluate the tracking resistance performance of insulating materials, Leakage Tracking Test Apparatus can accurately simulate the whole failure process of insulation components of electrical equipment such as leakage current generation, tracking expansion and insulation failure caused by surface contamination. Taking LISUN TTC-1 tracking tester as the research object, this paper expounds the working principle, design advantages, technical parameters and applicable standards of Leakage Tracking Test Apparatus, analyzes its application value in insulating material research and development, quality inspection and safety certification, and provides technical reference for insulating material selection, electrical product safety design and implementation of industrial standards.

1. Introduction
With the popularization of low-voltage electrical appliances, smart home equipment, new energy charging piles, photovoltaic power generation equipment and other products, solid insulating materials are core protective components of electrical equipment, and their moisture resistance, pollution resistance and tracking resistance directly affect the operational safety and service life of electrical products. In actual working environments, the surface of insulating materials easily absorbs dust, moisture, salt and other pollutants, which form conductive electrolyte under the action of alternating electric field and induce local leakage current. With the continuous action of current, carbonized conductive tracking channels will be formed on the material surface, which will eventually lead to insulation failure, equipment short circuit and even serious safety accidents such as fires.

To quantitatively evaluate the tracking resistance of insulating materials, standardized tests must be carried out by professional testing equipment, and Leakage Tracking Test Apparatus has become the mainstream testing equipment in the industry. This equipment reproduces real pollution and electric field coupling environment, and accurately measures the Comparative Tracking Index (CTI) and Proof Tracking Index (PTI) of materials, which is essential to control the quality of insulating materials and avoid electrical safety risks. As a mature and professional Leakage Tracking Test Apparatus, LISUN TTC-1 tracking tester fully complies with domestic and international relevant standards. Featuring high-precision regulation, automatic operation and perfect safety protection, it is widely used in enterprise research and development, factory quality inspection and third-party testing and certification institutions.

2. Working Principle and Testing Mechanism of Leakage Tracking Test Apparatus

2.1 Core Working Principle
The core working principle of Leakage Tracking Test Apparatus is electric field-chemical-thermal effect coupling simulation. Standard-sized insulating test samples are fixed on the test station, and high-purity platinum electrodes are used to clamp the samples and apply rated AC voltage. Standard 0.1% ammonium chloride contaminant solution is dripped evenly into the electrode gap to simulate humid and dusty pollution in natural environments. The equipment monitors the change of loop leakage current in real time, and records the whole process of tracking generation, carbonization expansion, continuous combustion and insulation breakdown of test samples.

By judging whether the sample produces continuous open flame, insulation breakdown or exceeds the threshold leakage current within specified dripping times, the CTI grade of materials can be accurately defined, and the tracking corrosion resistance of insulating materials can be quantified scientifically.

2.2 Failure Judgment Criteria
The built-in intelligent monitoring system of Leakage Tracking Test Apparatus adopts dual failure judgment standards. Firstly, the test is judged invalid when the leakage current exceeds 0.5A and lasts for more than 2 seconds. Secondly, once continuous non-self-extinguishing open flame appears on the sample surface, the equipment will immediately cut off power for protection. Meanwhile, the equipment synchronously records test duration, voltage fluctuation, current peak value and other experimental data, providing quantitative data basis for performance classification of insulating materials, which fully meets the judgment requirements of GB/T 4207-2022 and IEC 60112:2025 standards.

TTC-1 Tracking Test Chamber

3. Product Characteristics and Technical Parameters of LISUN TTC-1 Leakage Tracking Test Apparatus
LISUN TTC-1 series tracking tester includes standard cabinet type TTC-1 and cabinet-free type TTC-1S, which are professional Leakage Tracking Test Apparatus. Adopting high-precision voltage regulation and micro-current monitoring structure, it effectively solves the defects of traditional testing equipment such as large voltage deviation, insufficient dripping accuracy and large manual operation error, and meets the standardized testing requirements of various solid insulating materials.

3.1 Core Design Advantages
• High-precision Measurement and Control System: The adjustable AC voltage ranges from 100V to 600V with control accuracy of ±1%. The leakage current monitoring range is 0~100mA with detection accuracy of ±2%, and it is equipped with 60mA over-threshold acousto-optic alarm function to capture weak leakage signals efficiently.
• Standard Automatic Dripping Device: The dripping distance is adjustable within 30~40mm. The dripping rate and interval strictly follow international standards, eliminating time and dosage deviation caused by manual dripping and ensuring excellent test repeatability.
• High-purity Platinum Electrode Configuration: Equipped with PT999 high-purity platinum electrodes with purity higher than 99.9%. The electrode pressure is stably controlled at 1.0N±0.05N. The integrated design of electrodes and copper handles avoids test result errors caused by electrode oxidation and poor contact.
• Intelligent Control and Complete Safety Protection: It integrates flame recognition function and automatic power-off protection against over-current and short circuit. Equipped with large LCD touch screen, physical indicator lights and remote control operation, the test time is adjustable from 0s to 9999s, supporting automatic timing, manual pause and overtime shutdown.
• Sturdy Structure for Long-term Operation: The whole machine adopts high-temperature sprayed steel structure, which is high temperature resistant and anti-corrosive, suitable for long-term continuous laboratory testing and reducing equipment operation and maintenance costs.

3.2 Core Technical Parameter Table
The following table shows the detailed core technical parameters of LISUN TTC-1 series Leakage Tracking Test Apparatus:

3.3 Applicable Standard System
This Leakage Tracking Test Apparatus fully conforms to authoritative domestic and international standards, mainly including GB/T 4207-2022 Determination of Tracking and Erosion Resistance of Solid Insulating Materials and IEC 60112:2025 Method for Determination of Comparative Tracking Index of Solid Insulating Materials. For high-voltage working condition tests, users can upgrade to TTC-2 high-voltage model, which meets GB/T 6553-2024, IEC 60587:2022 and other high-voltage insulation test standards, covering full-scenario testing demands.

4. Industrial Application Fields of Leakage Tracking Test Apparatus
As core testing equipment for evaluating insulating material performance, Leakage Tracking Test Apparatus represented by TTC-1 is widely used in multiple industries, providing solid data support for material research and development, electrical product design and quality control.

4.1 Electronic and Household Appliance Industry
It is used for the testing of internal insulating plastic parts of household appliances such as refrigerators and washing machines, insulating shells of mobile phones and chargers, and insulating partition plates of electronic instruments. The Leakage Tracking Test Apparatus simulates humid household environment to verify the tracking resistance of insulating components, effectively avoiding hidden dangers such as equipment short circuit and spontaneous combustion caused by tracking aging, and ensuring the safety and compliance of household appliances.

4.2 Electrical Equipment Industry
It is applicable to the detection of wire and cable PVC/PE insulation layers, insulating bases of switches and sockets, relays, contactors and other low-voltage electrical insulation shells. By measuring the CTI grade of materials, the long-term tracking corrosion resistance of electrical accessories in service can be evaluated, meeting the access requirements of national and IEC standards, and improving the service life and operational stability of electrical products.

4.3 New Energy Industry
It is suitable for performance testing of insulating parts of charging piles, shell insulating materials of lithium batteries and insulating partition plates of photovoltaic inverters. Most new energy equipment is deployed in outdoor open environments and eroded by rainwater, dust and salt fog all year round. The Leakage Tracking Test Apparatus simulates complex service conditions to screen high-performance insulating materials with excellent tracking resistance, so as to strengthen the safety guarantee of new energy power utilization.

4.4 New Material Research and Development Field
It provides accurate test data for the research and development of ABS, PC, PA engineering plastics, insulating rubber, epoxy glass cloth board and other new solid insulating materials. Researchers can measure CTI values of materials with different formulas through Leakage Tracking Test Apparatus, compare the difference of tracking resistance before and after material modification, optimize material formula design, and meet testing standards such as UL 746A and ASTM D3638.

5. Conclusion and Prospect
Leakage Tracking Test Apparatus is an indispensable high-precision testing device for simulating humid and polluted environments and evaluating the tracking resistance of insulating materials. It reproduces actual service conditions from multiple dimensions including electric field environment, pollutant erosion and service duration, accurately measures core indicators such as CTI and PTI of insulating materials, and fundamentally eliminates potential safety hazards such as electric leakage, insulation breakdown and fire of electrical equipment.

As a mature and reliable Leakage Tracking Test Apparatus, LISUN TTC-1 tracking tester has outstanding advantages in precise voltage and current regulation, standardized automatic liquid dripping, high-purity electrode matching and comprehensive safety protection. It fully meets the requirements of domestic and international industrial standards and can satisfy testing demands in electronic appliances, electrical equipment, new energy and new material research fields.

In the future, electrical equipment will develop towards miniaturization, high power and outdoor installation, and the service environment of insulating materials will become harsher, which puts forward higher requirements for the precision, intelligence and multi-working condition compatibility of Leakage Tracking Test Apparatus. The equipment will be further upgraded in the directions of high-voltage integration, multi-stress coupling test and cloud data traceability, which will further promote the performance upgrading of insulating materials and the improvement of electrical product safety standards, and provide solid technical support for the high-quality development of the electrical industry.