In the field of overvoltage protection for power systems, zinc oxide surge arresters (MOA) serve as critical equipment for limiting lightning and operational overvoltages, and their operational status directly impacts the safety and stability of the power grid. As a core tool for online monitoring of the insulation degradation of surge arresters, the measurement accuracy and reliability of zinc oxide surge arrester resistive current testers are of paramount importance. Leveraging years of expertise in high-voltage testing technology, Wuhan Goldhome Hipot Electric Co., Ltd. offers the HM series of arrester testers. With core advantages such as high-precision measurement, wireless safety isolation, and intelligent data analysis, these devices provide professional testing solutions for power users worldwide. This article will comprehensively analyze the core advantages of Goldhome's zinc oxide arrester resistive current testers.
High-Precision Measurement and Intelligent Analysis Technology
The core strengths of Goldhome's resistive current testers lie in their advanced measurement principles and precise data analysis capabilities. The device employs a design that combines high-precision sampling circuits with Fourier harmonic analysis technology, enabling the precise extraction of the resistive component from the surge arrester's total current. Compared to traditional methods that monitor only total current, resistive current more sensitively reflects the moisture content and aging of the surge arrester's varistors-when the resistive current increases significantly by 15–30% from its normal value, it indicates a risk of arrester degradation.
The Goldhome tester features dual analysis capabilities using both fundamental and harmonic methods, capable of measuring multiple parameters including total current, resistive current, capacitive current, active power, reference voltage, and phase angle. The device achieves a measurement accuracy of ±(2% of reading + 5 μA), fully complying with the stringent requirements of DL/T 987-2017 "General Technical Conditions for Resistive Current Testers of Zinc Oxide Surge Arresters."
Wireless Isolation and Multi-Layer Safety Protection
To address the safety challenges of live testing on-site, the Goldhome tester employs wireless voltage signal acquisition technology. It uses high-speed digital magnetic isolation sensors to capture the reference voltage signal from the secondary side of the PT (potential transformer) and transmits it to the main unit via 433 MHz wireless communication, with an effective range exceeding 100 meters. This design achieves complete electrical isolation between the high- and low-voltage sides, completely eliminating the risk of high voltage being introduced through voltage test leads and ensuring operator safety.
The device features built-in dual protection against overvoltage and overcurrent. The input resistance of the current channel is ≤2Ω, while that of the voltage channel is ≥1800kΩ, ensuring stable and reliable performance under various operating conditions. Additionally, the instrument is equipped with a reliable grounding monitoring function that triggers an automatic alarm when grounding is absent.
Portable Design and Long Battery Life
Goldhome fully understands the stringent requirements for portability in field testing. Its resistive current tester features an integrated, portable design, with the entire unit weighing between 3 and 5 kg, and is equipped with a high-strength engineering plastic housing and a waterproof panel. The device is built with a high-capacity rechargeable lithium battery of over 7000 mAh, capable of continuous operation for 8–10 hours on a single charge, meeting the demands of all-day field testing.
The 7-inch TFT true-color LCD touchscreen simultaneously displays three-phase voltage and current waveforms, supports switching between Chinese and English interfaces, and offers intuitive and convenient operation.
Multifunctional Integration and Data Management
Goldhome testers support simultaneous single-phase or three-phase testing, automatically compensate for phase-to-phase interference, and accurately measure the resistive current and fundamental peak values of each phase. The device features a built-in micro-printer for on-site printing of test reports; it is equipped with an SD card slot and an RS485 communication port, supporting massive data storage and remote networking.
To accommodate different application scenarios, Goldhome offers multiple model options: the Basic model is suitable for routine inspections of 10–110 kV surge arresters, while the Professional model includes harmonic analysis capabilities to meet more demanding fault diagnosis requirements.
