Circuit Breaker & Switchgear Testing: Verifying low-resistance contacts in HV/MV/LV switchgear.
Power Transformer & Busbar Inspection: Measuring connection integrity in substations.
Cable & Conductor Joint Validation: Ensuring minimal resistance at splices and terminations.
Rail & Welding Quality Control: Assessing resistance of welded joints in industrial applications.
Preventive Maintenance & Commissioning: Essential for acceptance testing and routine diagnostics in power plants, grids, and industrial facilities.
KDZD300A cable outer sheath loop current grounding tester is applicable to the following specific measurement scenarios:
Detection of substation cable grounding system
Measure the circulating current of the metal sheath of high-voltage cable (such as aluminum sheath and copper shielding layer) in the single-end or cross interconnection grounding mode, and judge whether there are multipoint grounding, insulation damage or poor grounding faults.
Plant service power and transmission cable monitoring
Regular patrol inspection shall be carried out for the grounding current of the outer sheath of the power cable at the outlet of the generator, the low voltage side of the main transformer and the plant power distribution system to prevent cable overheating, insulation aging and other problems caused by large loop flow.
Operation and maintenance of urban underground cable tunnel/pipe gallery
Quickly detect the outer sheath grounding current and harmonic components of densely laid cables without interrupting the power supply, and evaluate cable operation and grounding system integrity.
Cable line fault diagnosis and preventive test
By measuring the circulating current, harmonic content (maximum 25 times), total harmonic distortion rate (THD) and other parameters, it can help judge the insulation deterioration of cable sheath, abnormal induced voltage or abnormal grounding circuit.
Analysis of harmonic interference
In places with nonlinear load (such as frequency converter and rectifier equipment), detect harmonic and inter-harmonic current in cable grounding circuit and evaluate its impact on system safety.
Leakage current and frequency monitoring
It is used to troubleshoot the leakage current to the ground caused by the damage of cable outer sheath, and monitor the system frequency stability (20Hz~400Hz wide frequency range, power frequency 45~65Hz high accuracy).
With non-contact, high anti-interference, portable and durable characteristics, the equipment is especially suitable for power operation and maintenance personnel to carry out fast, safe and accurate live detection and state evaluation on site.
This high-voltage switch comprehensive testing equipment can be widely used in the following typical scenarios:
1. Substation operation and maintenance
Conduct preventive tests or fault diagnosis on SF6 circuit breakers, vacuum switches, GIS, etc. in operation, quickly evaluate mechanical performance and contact status of contacts, and ensure the safety of the power grid.
2. Manufacturing and factory testing of high-voltage switches
In the production line or quality inspection process, full parameter testing is conducted on various types of circuit breakers (including graphite contacts, special structures with closing resistors, etc.) to ensure that the products comply with national standards and industry specifications.
3. Installation and commissioning of power engineering
In the construction or renovation of substation projects, perform functional verification on newly installed high-voltage switchgear before commissioning, including low voltage operation tests, synchronization tests, etc.
4. Electric power research and third-party testing institutions
Used for type testing, technical research, or certification testing, supporting high-precision data acquisition, waveform analysis, and report generation to meet the needs of professional laboratories.
5. Power distribution systems for large industrial and mining enterprises and self owned power plants
Regularly inspect internal high-voltage distribution equipment to promptly detect potential hazards such as contact wear, mechanism jamming, and abnormal circuit resistance, in order to avoid sudden power outages.
✅ The equipment can be used in conventional industrial environments with temperatures ranging from -10 ℃ to 40 ℃ and humidity ≤ 80% RH. It has excellent resistance to electromagnetic interference and can stably and accurately measure even in 500kV live substations, truly achieving "one operation, comprehensive diagnosis".
This high-voltage switch comprehensive testing system is mainly suitable for the following typical application scenarios:
1. Maintenance of power system substations
Conduct regular or post fault mechanical characteristic and circuit resistance tests on SF6 circuit breakers, vacuum switches, GIS combination devices, etc. in operation to ensure reliable opening and closing.
2. Factory inspection of high-voltage switch manufacturers
Used for full parameter quality inspection of various circuit breakers (vacuum, SF6, oil switches, etc.) on production lines, verifying whether the action time, speed, stroke, contact resistance, etc. meet the standards.
3. Installation and commissioning site of power engineering
In the construction of new substations or power grid renovation projects, perform functional verification and low voltage operation tests on newly installed high-voltage switchgear before commissioning.
4. Electric power research and testing institutions
Conduct performance research, type testing, or third-party certification testing on switchgear, and support high-precision data acquisition and waveform analysis.
5. Maintenance of power distribution systems in power plants and large industrial and mining enterprises
Conduct preventive tests on circuit breakers in self owned power plants or industrial high-voltage distribution cabinets to detect potential hazards such as mechanical jamming, contact wear, and poor circuit contact in advance.
✅ The equipment can work stably in a conventional industrial environment with a temperature range of -10 ℃ to 40 ℃ and a humidity of ≤ 80% RH. It has strong anti-interference ability and can accurately measure even near a 500kV live substation, meeting the testing needs of the entire life cycle from manufacturing, installation to operation and maintenance.
