Goldhome Technical Team Travels to Tianjin National Pipeline Network Group to Conduct On-Site Testing and Training for Ultra-Low-Frequency, Insulation Resistance, and DC Resistance Test Equipment
On March 15, 2024, the technical team from Wuhan Goldhome Hipot Electrical Co., Ltd. traveled to Tianjin and successfully completed on-site testing and operational training for multiple sets of equipment-including ultra-low-frequency high-voltage generators, insulation resistance testers, and DC resistance testers-at relevant units of the National Pipeline Network Group. The successful delivery of this project marks another significant achievement for Goldhome in the application of electrical testing equipment within the energy pipeline transportation industry.
Established in 2019, the National Oil and Gas Pipeline Network Group Co., Ltd. (hereinafter referred to as the National Pipeline Network Group) is a key state-owned enterprise under the supervision of the State-owned Assets Supervision and Administration Commission of the State Council, responsible for the unified construction and operation of the national oil and gas trunk pipeline network. Since its establishment, the National Pipeline Network Group has maintained a partnership with Tianjin characterized by a high degree of mutual trust and cooperation. In 2024, Tianjin Municipality and the National Pipeline Group signed a strategic cooperation framework agreement, under which the two parties are engaging in in-depth cooperation in areas such as the development of strategic emerging industries and energy infrastructure construction. The Group has successively established entities in Tianjin, including the LNG Receiving Terminal Management Company, the Storage and Transportation Technology Development Co., Ltd., the Engineering Technology Innovation Company, the General Research Institute, and the North China Company, among others. With nearly 3,000 employees in Tianjin, the Group has built a complete industrial chain spanning infrastructure, storage, transportation, and export, as well as technology R&D and customer service. The client served by Goldhome in this instance is precisely one of the key business segments of the National Pipeline Group's operations in Tianjin.
These on-site tests involved three core testing devices independently developed by Goldhome:
The ultra-low-frequency high-voltage generator is a specialized device developed by Goldhome to meet the insulation testing requirements for medium- and high-voltage cables. The device employs advanced digital frequency conversion technology and PWM (Pulse Width Modulation) technology, with the output frequency adjustable to three levels: 0.1 Hz, 0.05 Hz, and 0.02 Hz. With a peak voltage error of ≤3% and a waveform distortion rate of ≤5%, it fully meets the preventive testing requirements for 10 kV to 35 kV power cables. The unit features an 8-inch industrial-grade touchscreen that supports one-click test report generation and has a data storage capacity of up to 64 sets of measurement records. Notably, the unit includes a dielectric loss (tgδ) measurement function, enabling simultaneous measurement of the test specimen's dielectric loss factor, capacitance, and insulation resistance during AC withstand voltage tests, thereby providing multidimensional data support for equipment condition assessment. Optoelectronic control technology ensures complete isolation between high and low voltages, guaranteeing operator safety.
The insulation resistance tester is one of Goldhome's established product lines. The device requires no complex setup; operators can complete the entire process in just three steps: "select model-connect wires-test." The device is equipped with audible and visual alarms that automatically trigger when insulation values fall below standards. Its IP54 protection rating allows it to adapt to various challenging on-site environments.
The DC resistance tester is primarily used for precision measurements of DC resistance in transformer windings, high-power inductive equipment, and similar applications. The device employs a 32-bit ARM core as its processing unit, automatically performing self-calibration, constant-current detection, data processing, and resistance display. This test is a mandatory item in factory acceptance testing for semi-finished and finished transformers, as well as during installation, handover, and preventive testing.
During the on-site testing phase, Goldhome technical engineers strictly followed standardized procedures to sequentially complete the on-site wiring and system integration of the three devices. For the ultra-low-frequency high-voltage generator, the engineers selected a typical on-site power cable as the test specimen and sequentially performed a 0.1 Hz ultra-low-frequency AC withstand voltage test, simultaneously measuring the cable's dielectric loss factor, capacitance, and insulation resistance. All performance indicators of the equipment met the design requirements. For the insulation resistance tester, the engineers conducted insulation resistance tests on each phase of the cable using different voltage levels, yielding stable and reliable data. Regarding the DC resistance tester, the engineers performed precise measurements of the DC resistance of the windings in critical equipment, demonstrating excellent measurement accuracy and data stability. All test items passed on the first attempt.
