Yitai ETCR9740A/ETCR9740B Zinc Oxide Arrester Live Tester
The "Yitai ETCR9740A/ETCR9740B Zinc Oxide Arrester Live Tester" you mentioned is a core precision instrument used in power systems to evaluate the operating status of arresters. Considering your location in the Jiangsu Yangzhou industrial belt and the mainstream technology in the industry, here is a summary of the core functions, technical features, and selection points of this series of live testers:
1. Core Functions and Testing Principles
This tester is specifically designed to detect the electrical performance of zinc oxide arresters (MOA) in operation without power outage. Its core principle is to measure and analyze the total leakage current of the arrester, separate the resistive current component, and thereby accurately determine whether the arrester is damp inside, whether the valve plates are aged, or if there is internal damage.
2. Core Technical Features
Live/De-energized Compatibility: It is not only suitable for online live monitoring of arresters in operation but also supports detection in de-energized states, and can even be used in laboratory environments.
Flexible Signal Acquisition Methods:
Current Sampling: Supports using a high-precision current clamp (wireless or wired) to clamp onto the arrester's grounding down conductor, or directly connecting to both ends of the arrester's discharge counter for sampling.
Voltage Reference Sampling: Supports multiple synchronization methods, including taking three-phase/B-phase voltage from the PT secondary side, using an induction plate to measure electric field strength, and a "voltage-free software simulation" mode that does not require an external voltage signal.
Three-Phase Simultaneous Measurement and Anti-Interference: Supports simultaneous testing of three-phase current and three-phase voltage, greatly improving work efficiency. Built-in anti-interference calculation function and angle compensation function effectively solve the problem of mutual interference among three phases of arresters at voltage levels of 220kV and above.
Intelligent and Portable Design: Equipped with a high-definition color touch screen, built-in large-capacity lithium battery (supports long continuous operation), especially suitable for field use without power supply. Supports Bluetooth connection to mobile phone/tablet APP control, USB export of Word format reports, and on-site thermal printing.
3. Key Test Parameter References
Measurement Range: The total current/resistive current measurement range is typically 0-20mA (expandable), and the voltage acquisition range is 30-250V.
Measurement Accuracy: When the total current is greater than 100μA, the current measurement accuracy can typically reach ±5% of reading ±1 digit.
Analysis Dimensions: Can display total current waveform, fundamental RMS value, peak value, as well as the 1st, 3rd, 5th, 7th, and 9th harmonic RMS values of resistive current, positive and negative peak values, phase angle difference, and active power consumption, etc.
4. On-Site Operation and Safety Regulations
Safety Isolation: Before live testing, a live work permit must be obtained, and safety isolation measures must be implemented.
Wiring Specifications: If using the PT wiring mode, ensure that the voltage signal is taken from a PT that is from the same source and same phase as the arrester, and strictly prevent short circuits on the PT secondary side; if using a current clamp, ensure the clamp jaw is clean and fully closed, and the direction mark is uniformly oriented toward the arrester body.
Reliable Grounding: The instrument's grounding wire must be reliably connected to a ground grid with good conductivity; otherwise, it will affect measurement accuracy and even endanger personal safety.
💡 Further Assistance
The zinc oxide arrester live tester is a key device for achieving equipment condition-based maintenance and preventing grid accidents. May I ask what your specific needs are currently:
Product Selection and Parameter Verification: Do you need to confirm the specific configuration differences between ETCR9740A and ETCR9740B, or evaluate whether their wireless transmission distance and battery life meet your on-site working conditions?
On-Site Operation and Wiring Guidance: Do you need to understand the specific wiring steps and parameter setting methods for this instrument in "voltage-free mode" or "three-phase simultaneous measurement mode"?
Data Analysis and Fault Diagnosis: Have you obtained data in actual testing and need assistance in judging whether the arrester has defects based on the growth trend of resistive current or the symmetry of three-phase data?
