Handheld MOA Resistive Current Tester | VS-400S
Products Details
VS-400S Handheld MOA Resistive Current Tester is designed for modern power system maintenance, providing accurate field diagnostics of zinc oxide surge arresters (MOA) under live or offline operating conditions. It plays a critical role in evaluating insulation performance and aging status across high-voltage transmission networks, distribution systems, and substations. As a core diagnostic instrument within our lightning arrester tester lineup, it delivers comprehensive evaluation metrics for grid surge protection equipment.
The instrument integrates high-speed digital signal processing (DSP) and advanced Fourier harmonic analysis algorithms. This technology allows precise separation of the total leakage current into its resistive and capacitive components, enabling maintenance engineers to accurately evaluate degradation, moisture ingress, and thermal stress in metal oxide arresters.
A key advantage of the VS-400S is its flexible reference voltage acquisition system. It supports multiple input methods, including PT secondary voltage, 220V maintenance power supply, and electric field induction plate measurement. Both wired and wireless communication modes are available, allowing stable operation in complex substation environments.
The device supports single-phase and three-phase simultaneous measurement, enabling complete monitoring of A, B, and C phase surge arresters in a single test cycle. Its advanced automatic edge compensation algorithm helps eliminate phase interference caused by spatial coupling effects in closely installed arrester arrays.
Equipped with a 7-inch high-brightness color LCD touchscreen, the VS-400S provides clear visualization of real-time waveforms, harmonic spectra, phase angles, and measurement parameters. The ergonomic handheld design ensures portability while maintaining the full functionality of a professional-grade diagnostic system.
Built-in data storage supports up to 512 test records, with USB export, Bluetooth, and RS232 communication for easy data management. An integrated thermal printer enables immediate field report generation on-site. Powered by a high-capacity lithium battery supporting up to 8 hours of continuous operation, the VS-400S is ideal for field engineers working in substations and distribution lines.
Features
| Feature | Description |
| Handheld Design | Lightweight portable structure for field operation |
| Multi-Parameter Measurement | Total current, resistive current, voltage, harmonics |
| Fourier Harmonic Analysis | High-precision waveform decomposition technology |
| Multiple Reference Modes | PT, 220V power supply, and electric field induction |
| Wireless & Wired Communication | Flexible data transmission in complex environments |
| Three-Phase Measurement | Simultaneous A/B/C phase testing capability |
| Auto Edge Compensation | Reduces phase interference in field conditions |
| 7-Inch Color Touchscreen | High visibility display for outdoor use |
| Built-in Thermal Printer | Instant report printing on site |
| Data Storage | Stores up to 512 test records |
| Multi-Interface Export | USB / Bluetooth / RS232 supported |
| Long Battery Life | Up to 8 hours continuous field operation |
| Item | Specification |
| Model | VS-400S |
| Leakage Current Range | 0.1 mA – 10 mA |
| Reference Voltage Input | 25V – 300V AC (50/60Hz) |
| Electric Field Range | 30 kV/m – 300 kV/m |
| Current Accuracy | ±(5% reading + 5 μA) |
| Voltage Accuracy | ±(5% reading + 0.5 V) |
| Harmonic Accuracy | ±10% |
| Display | 7-inch color LCD touchscreen |
| Data Storage | 512 groups |
| Communication | USB / RS232 / Bluetooth |
| Printing | Built-in thermal printer |
| Power Supply | Lithium battery / AC charger |
| Working Time | ≥ 8 hours |
Product Guide
1. Preparation
Connect the grounding terminal securely to earth ground. Attach the current clamps to the bottom ground wire of the MOA arrester. Select the appropriate reference voltage method (PT secondary, wireless transmission, or electric field induction plate).
2. Startup
Power on the device and wait for system initialization. Select the desired test mode and phase configuration (single-phase or three-phase testing).
3. Configuration
Set the reference source, PT transformation ratio, compensation mode (disabled, manual, or auto edge compensation), and specific test parameters.
4. Measurement
Initiate the measurement. The instrument automatically processes signals and calculates total current, resistive current, harmonic components, and phase angles in real time.
5. Data Handling
Store test records in internal memory, print hard-copy reports using the built-in thermal printer, or export data via USB or Bluetooth for review.
6. Shutdown
Save all active test data, stop measurement, power off the instrument safely, and disconnect test leads.
Applications
The VS-400S is widely used in:
- Substation surge arrester condition monitoring
- High-voltage transmission line maintenance
- Distribution network insulation inspection
- MOA aging and failure diagnosis
- Preventive maintenance of power systems
- Industrial electrical safety testing
- Utility and EPC contractor field inspection
Weshine Advantages
Weshine Electric is a specialized manufacturer of high-voltage electrical testing and diagnostic equipment, offering reliable field instruments for global utilities.
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Advanced Measurement Technology: Integrates high-speed DSP and Fourier harmonic analysis to ensure accurate separation of resistive and capacitive current components.
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Strong Field Adaptability: Designed for complex substation environments with support for wired, wireless, and induction-based reference voltage acquisition.
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Handheld Portability: Ergonomic, lightweight structure improves field mobility without sacrificing diagnostic precision.
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High Anti-Interference Performance: Advanced filtering and edge compensation algorithms eliminate spatial electromagnetic interference during live line testing.
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Multi-Phase Testing Efficiency: Simultaneous three-phase testing significantly reduces on-site diagnostic time.
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Comprehensive System Integration: Seamlessly complements our flagship lightning arrester tester and ground earth resistance tester solutions to provide complete substation safety assessment.
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Global Application Experience: Field-proven performance across power grids, utilities, and industrial complexes worldwide.
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Reliable After-Sales Support: Provides comprehensive technical guidance, factory calibration services, and long-term maintenance assistance.